Records |
Author |
Sebhatu, K.T.; Gezahegn, T.W.; Berhanu, T.; Maertens, M.; Van Passel, S.; D'Haese, M. |
Title |
Exploring variability across cooperatives : economic performance of agricultural cooperatives in northern Ethiopia |
Type |
A1 Journal article |
Year |
2021 |
Publication |
The international food and agribusiness management review |
Abbreviated Journal |
|
Volume |
24 |
Issue |
3 |
Pages |
397-419 |
Keywords |
A1 Journal article; Engineering Management (ENM) |
Abstract |
The number of agricultural cooperatives increased quickly in Ethiopia since the 1990s. While many papers studied the impact of membership of Ethiopian cooperatives, not much is known on their performance. This study takes a cooperative-level perspective which is unique in an African context. It compares the economic performance proxied by sales revenue and profit of a wide range of agricultural cooperatives in northern Ethiopia. Data were collected from 511 agricultural cooperatives in 12 districts of Tigray. The contributing factors of the performance are analyzed with Ordinary Least Squares regression (OLS) and Heckman selection models. Our results underscore the importance of membership size, total assets, presence of conflict among members, and union membership. Chairperson characteristics and the internal organization of a cooperative seem to be less correlated to performance. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000645416400002 |
Publication Date |
2021-03-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1096-7508; 1559-2448 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:179025 |
Serial |
6923 |
Permanent link to this record |
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Author |
Sharafi, L.; Zarafshani, K.; Keshavarz, M.; Azadi, H.; Van Passel, S. |
Title |
Farmers' decision to use drought early warning system in developing countries |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Science Of The Total Environment |
Abbreviated Journal |
Sci Total Environ |
Volume |
758 |
Issue |
|
Pages |
142761 |
Keywords |
A1 Journal article; Engineering Management (ENM) |
Abstract |
Drought is a persistent, sluggish natural disaster in developing countries that has generated a financial burden and an unstable climate. Farmers should adopt early warning systems (EWS) in their strategies for monitoring drought to reduce its serious consequences. However, farmers in developing countries are reluctant to use EWS as their management strategies. Hence, the aim of this study was to investigate the decision of farmers to use climate knowledge through the model of farming activity in Kermanshah Township, Iran. A surveyor questionnaire was used to gather data from 370 wheat farmers using random sampling methods inmulti-stage clusters. Results revealed that the decision to use climate information is affected by personal factors, attitude towards climate information, objectives of using climate information, and external/physical farming factors. The result of this study has implications for drought management practitioners. To be specific, the results can aid policymakers to design early alert programs to minimize the risk of drought and thus move from conventional to climate smart agriculture. (C) 2020 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000605623800001 |
Publication Date |
2020-10-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0048-9697 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.9 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 4.9 |
Call Number |
UA @ admin @ c:irua:176030 |
Serial |
6924 |
Permanent link to this record |
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Author |
Van Schoubroeck, S.; Thomassen, G.; Van Passel, S.; Malina, R.; Springael, J.; Lizin, S.; Venditti, R.A.; Yao, Y.; Van Dael, M. |
Title |
An integrated techno-sustainability assessment (TSA) framework for emerging technologies |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Green Chemistry |
Abbreviated Journal |
Green Chem |
Volume |
23 |
Issue |
4 |
Pages |
1700-1715 |
Keywords |
A1 Journal article; Economics; Engineering sciences. Technology; Engineering Management (ENM) |
Abstract |
A better understanding of the drivers of the economic, environmental, and social sustainability of emerging (biobased) technologies and products in early development phases can help decision-makers to identify sustainability hurdles and opportunities. Furthermore, it guides additional research and development efforts and investment decisions, that will, ultimately, lead to more sustainable products and technologies entering a market. To this end, this study developed a novel techno-sustainability assessment (TSA) framework with a demonstration on a biobased chemical application. The integrated TSA compares the potential sustainability performance of different (technology) scenarios and helps to make better-informed decisions by evaluating and trading-off sustainability impacts in one holistic framework. The TSA combines methods for comprehensive indicator selection and integration of technological and country-specific data with environmental, economic, and social data. Multi-criteria decision analysis (MCDA) is used to address data uncertainty and to enable scenario comparison if indicators are expressed in different units. A hierarchical, stochastic outranking approach is followed that compares different weighting schemes and preference structures to check for the robustness of the results. The integrated TSA framework is demonstrated on an application for which the sustainability of a production and harvesting plant of microalgae-based food colorants is assessed. For a set of scenarios that vary with regard to the algae feedstock, production technology, and location, the sustainability performance is quantified and compared, and the underlying reasons for this performance are explored. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000629630600018 |
Publication Date |
2021-02-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1463-9262; 1463-9270 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.125 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 9.125 |
Call Number |
UA @ admin @ c:irua:175716 |
Serial |
6931 |
Permanent link to this record |
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Author |
Tschulkow, M.; Compernolle, T.; Van Passel, S. |
Title |
Optimal timing of multiple investment decisions in a wood value chain : a real options approach |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Journal Of Environmental Management |
Abbreviated Journal |
J Environ Manage |
Volume |
290 |
Issue |
|
Pages |
112590 |
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
Abstract |
A new reductive catalytic fractionation biorefinery process (RCF) is currently being developed transforming wood into high-value end-products. RCF is considered to be in the pilot stage with a technology readiness level of 5–6. Apart from the RCF-process characteristics, the economic feasibility also depends on the investment decisions that are made upstream and downstream within the wood value chain, increasing the level of uncertainty. Two investment options within the value chain are considered: an option to invest in harvesting equipment and an option to invest in the RCF. To understand the impact of multiple sources of uncertainty on the decision to invest in an innovative RCF-driven wood value chain, an analytical two-factor real options model is presented, accounting for correlated cost and price uncertainties. Two different scenarios, separated and united investments in harvesting equipment and RCF, are analyzed. In both scenarios, market uncertainty postpones investment in comparison to the traditional NPV approach. When both investments are considered separately, the investment in RCF is expected to be earlier than the investment in harvesting equipment. When both investment decisions are united, the probability of investment increases. The study reveals that RCF has the potential to stimulate investments from different investors, –upstream and midstream–, within the wood value chain. Besides, the introduced real options model proofs its ability to assess the economic feasibility of innovative technologies (e.g RCF) individually or within the value chain, taking into account multiple sources of uncertainty. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000656438000005 |
Publication Date |
2021-04-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0301-4797 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
4.01 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 4.01 |
Call Number |
UA @ admin @ c:irua:179487 |
Serial |
6937 |
Permanent link to this record |
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Author |
Azadi, H.; Moghaddam, S.M.; Burkart, S.; Mahmoudi, H.; Van Passel, S.; Kurban, A.; Lopez-Carr, D. |
Title |
Rethinking resilient agriculture : from Climate-Smart Agriculture to Vulnerable-Smart Agriculture |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Journal Of Cleaner Production |
Abbreviated Journal |
J Clean Prod |
Volume |
319 |
Issue |
|
Pages |
128602 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM) |
Abstract |
Climate-Smart Agriculture (CSA) is seeking to overcome the food security problem and develop rural livelihoods while minimizing negative impacts on the environment. However, when such synergies exist, the situation of small-scale farmers is often overlooked, and they are unable to implement new practices and technologies. Therefore, the main aim of this study is to improve CSA by adding the neglected but very important element “small-scale farmer”, and introduce Vulnerable-Smart Agriculture (VSA) as a complete version of CSA. VSA indicates, based on the results of this study, that none of the decisions made by policymakers can be realistic and functional as long as the voice of the farmers influenced by their decisions is not heard. Therefore, to identify different levels for possible interventions and develop VSA monitoring indicators, a new conceptual framework needs to be developed. This study proposed such a framework consisting of five elements: prediction of critical incidents by farmers, measuring the consequences of incidents, identifying farmers' coping strategies, assessing farmers' livelihood capital when facing an incident, and adapting to climate incidents. The primary focus of this study is on farmers' learning and operational preparation to deal with tension and disasters at farm level. Understanding the implications of threats from climate change and the recognizing of coping mechanisms will contribute to an increase in understanding sustainable management. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000728681500005 |
Publication Date |
2021-08-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0959-6526 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.715 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 5.715 |
Call Number |
UA @ admin @ c:irua:184869 |
Serial |
6942 |
Permanent link to this record |
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Author |
Gezahegn, T.W.; Van Passel, S.; Berhanu, T.; D'Haese, M.; Maertens, M. |
Title |
Structural and institutional heterogeneity among agricultural cooperatives in Ethiopia : does it matter for farmers' welfare? |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Journal Of Agricultural And Resource Economics |
Abbreviated Journal |
J Agr Resour Econ |
Volume |
46 |
Issue |
2 |
Pages |
325-342 |
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
Abstract |
This paper analyzes how structural and institutional heterogeneity among irrigation cooperatives shapes the impact of membership on farmers' welfare in northern Ethiopia, using a novel heteroskedasticity-based identification strategy. More specifically, we estimate how cooperative characteristics influence members' income and poverty level. We find that stricter water use regulations have income-enhancing and poverty-reducing effects for farmers. We also find that farmers benefit more from membership in larger, younger, and bottom-up cooperatives initiated through grassroots collective action. Our findings have implications for irrigation development in Ethiopia and call for a better deliberation of organizational heterogeneity in cooperative impact studies |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000656121100010 |
Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1068-5502; 2327-8285 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
1 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 1 |
Call Number |
UA @ admin @ c:irua:179190 |
Serial |
6945 |
Permanent link to this record |
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Author |
Larraín, M.; Van Passel, S.; Thomassen, G.; Van Gorp, B.; Nhu, T.T.; Huysveld, S.; Van Geem, K.M.; De Meester, S.; Billen, P. |
Title |
Techno-economic assessment of mechanical recycling of challenging post-consumer plastic packaging waste |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Resources Conservation And Recycling |
Abbreviated Journal |
Resour Conserv Recy |
Volume |
170 |
Issue |
|
Pages |
105607 |
Keywords |
A1 Journal article; Economics; Engineering sciences. Technology; Engineering Management (ENM); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS) |
Abstract |
Increasing plastic recycling rates is crucial to tackle plastic pollution and reduce consumption of fossil resources. Recycling routes for post-consumer plastic fractions that are technologically and economically feasible remain a challenge. Profitable value chains for recycling mixed film and tray-like plastics have hardly been implemented today, in sharp contrast to recycling of relatively pure fractions such as polyethylene terephthalate and high-density polyethylene bottles. This study examines the economic feasibility of implementing mechanical recycling for plastic waste such as polypropylene, polystyrene, polyethylene films and mixed polyolefins. In most European countries these plastic fractions are usually incinerated or landfilled whilst in fact technologies exist to mechanically recycle them into regranulates or regrinds. Results show that the economic incentives for the recycling of plastic packaging depend predominantly on the product price and product yield. At current price levels, the most profitable plastic fraction to be recycled is PS rigids, with an internal rate of return of 14%, whereas the least profitable feed is a mixed polyolefin fraction with a negative internal rate of return in a scenario with steadily rising oil prices. Moreover, these values would be substantially reduced if oil prices, and therefore plastic product prices decrease. Considering a discount rate of 15% for a 15-year period, mechanical recycling is not profitable if no policy changes would be imposed by governments. Clearly low oil prices may jeopardize the mechanical recycling industry, inducing the need for policies that would increase the demand of recycled products such as imposing minimal recycled content targets. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000667309200042 |
Publication Date |
2021-04-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0921-3449 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.313 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 3.313 |
Call Number |
UA @ admin @ c:irua:177325 |
Serial |
6946 |
Permanent link to this record |
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Author |
Pramanik, G.; Kvakova, K.; Thottappali, M.A.; Rais, D.; Pfleger, J.; Greben, M.; El-Zoka, A.; Bals, S.; Dracinsky, M.; Valenta, J.; Cigler, P. |
Title |
Inverse heavy-atom effect in near infrared photoluminescent gold nanoclusters |
Type |
A1 Journal Article |
Year |
2021 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
Volume |
13 |
Issue |
23 |
Pages |
10462-10467 |
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
Abstract |
Fluorophores functionalized with heavy elements show enhanced intersystem crossing due to increased spin–orbit coupling, which in turn shortens the fluorescence decay lifetime (<italic>τ</italic><sup>PL</sup>). This phenomenon is known as the heavy-atom effect (HAE). Here, we report the observation of increased<italic>τ</italic><sup>PL</sup>upon functionalisation of near-infrared photoluminescent gold nanoclusters with iodine. The heavy atom-mediated increase in<italic>τ</italic><sup>PL</sup>is in striking contrast with the HAE and referred to as inverse HAE. Femtosecond and nanosecond transient absorption spectroscopy revealed overcompensation of a slight decrease in lifetime of the transition associated with the Au core (ps) by a large increase in the long-lived triplet state lifetime associated with the Au shell, which contributed to the observed inverse HAE. This unique observation of inverse HAE in gold nanoclusters provides the means to enhance the triplet excited state lifetime. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2021-05-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2040-3364 |
ISBN |
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Additional Links |
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Impact Factor |
7.367 |
Times cited |
7 |
Open Access |
OpenAccess |
Notes |
The authors acknowledge support from GACR project Nr.18- 12533S. G. P. acknowledges support from EUSMI project No. E180200060; J.P. from the Ministry of Education, Youth and Sports of the Czech Republic – Program INTER-EXCELLENCE (LTAUSA19066). |
Approved |
Most recent IF: 7.367 |
Call Number |
EMAT @ emat @ |
Serial |
6950 |
Permanent link to this record |
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Author |
Mallick, S.; Zhang, W.; Batuk, M.; Gibbs, A.S.; Hadermann, J.; Halasyamani, P.S.; Hayward, M.A. |
Title |
The crystal and defect structures of polar KBiNb2O7 |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
Volume |
51 |
Issue |
5 |
Pages |
1866-1873 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
KBiNb2O7 was prepared from RbBiNb2O7 by a sequence of cation exchange reactions which first convert RbBiNb2O7 to LiBiNb2O7, before KBiNb2O7 is formed by a further K-for-Li cation exchange. A combination of neutron, synchrotron X-ray and electron diffraction data reveal that KBiNb2O7 adopts a polar, layered, perovskite structure (space group A11m) in which the BiNb2O7 layers are stacked in a (0, ½, z) arrangement, with the K+ cations located in half of the available 10-coordinate interlayer cation sites. The inversion symmetry of the phase is broken by a large displacement of the Bi3+ cations parallel to the y-axis. HAADF-STEM images reveal that KBiNb2O7 exhibits frequent stacking faults which convert the (0. ½, z) layer stacking to (½, 0, z) stacking and vice versa, essentially switching the x- and y-axes of the material. By fitting the complex diffraction peak shape of the SXRD data collected from KBiNb2O7 it is estimated that each layer has approximately an ~11% chance of being defective – a high level which is attributed to the lack of cooperative NbO6 tilting in the material, which limits the lattice strain associated with each fault. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000741540300001 |
Publication Date |
2022-01-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1477-9226 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
4 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
Experiments at the Diamond Light Source were performed as part of the Block Allocation Group award “Oxford/Warwick Solid State Chemistry BAG to probe composition-structure-property relationships in solids” (EE18786). Experiments at the ISIS pulsed neutron facility were supported by a beam time allocation from the STFC (RB 2000148). SM thanks Somerville College for an Oxford Ryniker Lloyd scholarship. PSH and WZ thank the National Science Foundation (DMR-2002319) for support. |
Approved |
Most recent IF: 4 |
Call Number |
EMAT @ emat @c:irua:185504 |
Serial |
6951 |
Permanent link to this record |
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Author |
Veronesi, S.; Pfusterschmied, G.; Fabbri, F.; Leitgeb, M.; Arif, O.; Esteban, D.A.; Bals, S.; Schmid, U.; Heun, S. |
Title |
3D arrangement of epitaxial graphene conformally grown on porousified crystalline SiC |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
189 |
Issue |
|
Pages |
210-218 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000760358800008 |
Publication Date |
2021-12-17 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0008-6223 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
10.9 |
Times cited |
3 |
Open Access |
OpenAccess |
Notes |
Horizon 2020; European Commission; Horizon 2020 Framework Programme; European Research Council, 128 731 019 ; European Research Council, REALNANO 815 128 ; sygmaSB |
Approved |
Most recent IF: 10.9 |
Call Number |
EMAT @ emat @c:irua:186583 |
Serial |
6952 |
Permanent link to this record |
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Author |
Van Everbroeck, T.; Wu, J.; Arenas-Esteban, D.; Ciocarlan, R.-G.; Mertens, M.; Bals, S.; Dujardin, C.; Granger, P.; Seftel, E.M.; Cool, P. |
Title |
ZnAl layered double hydroxide based catalysts (with Cu, Mn, Ti) used as noble metal-free three-way catalysts |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Applied clay science |
Abbreviated Journal |
Appl Clay Sci |
Volume |
217 |
Issue |
|
Pages |
106390 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000795870100004 |
Publication Date |
2022-01-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0169-1317 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.6 |
Times cited |
6 |
Open Access |
OpenAccess |
Notes |
The authors acknowledge financial support by theEuropean Union’s Horizon 2020 Project Partial-PGMs (H2020-NMP-686086). R-G C. and P.C. acknowledge the FWO-Flanders (project no. G038215N) for financial support. S⋅B and D.A.E thank the financial support of the European Research Council (ERC-CoG-2019 815128). The authors are grateful to Johnson Matthey, UK, for supplying the commercial benchmark catalysts; realnano; sygmaSB |
Approved |
Most recent IF: 5.6 |
Call Number |
EMAT @ emat @c:irua:186956 |
Serial |
6955 |
Permanent link to this record |
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Author |
Heyvaert, W.; Pedrazo-Tardajos, A.; Kadu, A.; Claes, N.; González-Rubio, G.; Liz-Marzán, L.M.; Albrecht, W.; Bals, S. |
Title |
Quantification of the Helical Morphology of Chiral Gold Nanorods |
Type |
A1 Journal article |
Year |
2022 |
Publication |
ACS materials letters |
Abbreviated Journal |
ACS Materials Lett. |
Volume |
4 |
Issue |
|
Pages |
642-649 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Chirality in inorganic nanoparticles and nanostructures has gained increasing scientific interest, because of the possibility to tune their ability to interact differently with left- and right-handed circularly polarized light. In some cases, the optical activity is hypothesized to originate from a chiral morphology of the nanomaterial. However, quantifying the degree of chirality in objects with sizes of tens of nanometers is far from straightforward. Electron tomography offers the possibility to faithfully retrieve the three-dimensional morphology of nanomaterials, but only a qualitative interpretation of the morphology of chiral nanoparticles has been possible so far. We introduce herein a methodology that enables us to quantify the helicity of complex chiral nanomaterials, based on the geometrical properties of a helix. We demonstrate that an analysis at the single particle level can provide significant insights into the origin of chiroptical properties. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000784490000013 |
Publication Date |
2022-03-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2639-4979 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
11 |
Open Access |
OpenAccess |
Notes |
S.B. and A.P.-T. gratefully acknowledge funding by the European Research Council (ERC Consolidator Grant #815128-REALNANO) the European Union’s Horizon 2020 research and innovation program under grant agreement #823717ESTEEM3. L.M.L.-M. acknowledges funding from MCIN/ AEI /10.13039/501100011033, grant # PID2020- 117779RB-I00 and the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant No. MDM-2017-0720). G.G.-R. thanks the Spanish Spanish Ministerio de Ciencia e Innovación for an FPI (BES-2014- 068972) fellowship.; SygmaSB; esteem3reported; esteem3jra |
Approved |
Most recent IF: NA |
Call Number |
EMAT @ emat @c:irua:186959 |
Serial |
6956 |
Permanent link to this record |
|
|
|
Author |
Ning, S.; Xu, W.; Ma, Y.; Loh, L.; Pennycook, T.J.; Zhou, W.; Zhang, F.; Bosman, M.; Pennycook, S.J.; He, Q.; Loh, N.D. |
Title |
Accurate and Robust Calibration of the Uniform Affine Transformation Between Scan-Camera Coordinates for Atom-Resolved In-Focus 4D-STEM Datasets |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
Volume |
|
Issue |
|
Pages |
1-11 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Accurate geometrical calibration between the scan coordinates and the camera coordinates is critical in four-dimensional scanning transmission electron microscopy (4D-STEM) for both quantitative imaging and ptychographic reconstructions. For atomic-resolved, in-focus 4D-STEM datasets, we propose a hybrid method incorporating two sub-routines, namely a J-matrix method and a Fourier method, which can calibrate the uniform affine transformation between the scan-camera coordinates using raw data, without a priori knowledge about the crystal structure of the specimen. The hybrid method is found robust against scan distortions and residual probe aberrations. It is also effective even when defects are present in the specimen, or the specimen becomes relatively thick. We will demonstrate that a successful geometrical calibration with the hybrid method will lead to a more reliable recovery of both the specimen and the electron probe in a ptychographic reconstruction. We will also show that, although the elimination of local scan position errors still requires an iterative approach, the rate of convergence can be improved, and the residual errors can be further reduced if the hybrid method can be firstly applied for initial calibration. The code is made available as a simple-to-use tool to correct affine transformations of the scan-camera coordinates in 4D-STEM experiments. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000767045700001 |
Publication Date |
2022-03-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1431-9276 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.8 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
N. D. Loh kindly acknowledges support from NUS Early Career Research Award (R-154-000-B35-133), MOE’s AcRF Tier 1 grant nr. R-284-000-172-114 and NRF CRP grant number NRF-CRP16-2015-05. Q. He would also like to acknowledge the support of the National Research Foundation (NRF) Singapore, under its NRF Fellowship (NRF-NRFF11-2019-0002). W. Zhou acknowledges the support from Beijing Outstanding Young Scientist Program (BJJWZYJH01201914430039). F. Zhang acknowledges the support of the National Natural Science Foundation of China (11775105, 12074167). T. J. Pennycook acknowledges funding under the European Union’s Horizon 2020 research and innovation programme from the European Research Council (ERC) Grant agreement No. 802123-HDEM. |
Approved |
Most recent IF: 2.8 |
Call Number |
EMAT @ emat @c:irua:186958 |
Serial |
6957 |
Permanent link to this record |
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|
|
Author |
Missen, O.P.; Mills, S.J.; Canossa, S.; Hadermann, J.; Nenert, G.; Weil, M.; Libowitzky, E.; Housley, R.M.; Artner, W.; Kampf, A.R.; Rumsey, M.S.; Spratt, J.; Momma, K.; Dunstan, M.A. |
Title |
Polytypism in mcalpineite : a study of natural and synthetic Cu₃TeO₆ |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials (Online) |
Abbreviated Journal |
Acta Crystallogr B |
Volume |
78 |
Issue |
1 |
Pages |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Synthetic and naturally occurring forms of tricopper orthotellurate, (Cu3TeO6)-Te-II-O-IV (the mineral mcalpineite) have been investigated by 3D electron diffraction (3D ED), X-ray powder diffraction (XRPD), Raman and infrared (IR) spectroscopic measurements. As a result of the diffraction analyses, (Cu3TeO6)-Te-II-O-IV is shown to occur in two polytypes. The higher-symmetric (Cu3TeO6)-Te-II-O-IV-1C polytype is cubic, space group 1a (3) over bar, with a = 9.537 (1) angstrom and V = 867.4 (3) angstrom(3) as reported in previous studies. The 1C polytype is a well characterized structure consisting of alternating layers of (CuO6)-O-II octahedra and both (CuO6)-O-II and (TeO6)-O-VI octahedra in a patchwork arrangement. The structure of the lower-symmetric orthorhombic (Cu3TeO6)-Te-II-O-IV-2O polytype was determined for the first time in this study by 3D ED and verified by Rietveld refinement. The 2O polytype crystallizes in space group Pcca, with a = 9.745 (3) angstrom, b = 9.749 (2) angstrom, c = 9.771 (2) angstrom and V = 928.3 (4) angstrom(3) . High-precision XRPD data were also collected on (Cu3TeO6)-Te-II-O-IV-2O to verify the lower-symmetric structure by performing a Rietveld refinement. The resultant structure is identical to that determined by 3D ED, with unit-cell parameters a = 9.56157 (19) angstrom, b = 9.55853 (11) angstrom, c = 9.62891 (15) angstrom and V = 880.03 (2) angstrom(3) . The lower symmetry of the 2O polytype is a consequence of a different cation ordering arrangement, which involves the movement of every second (CuO6)-O-II and (TeO6)-O-VI octahedral layer by (1/4, 1/4, 0), leading to an offset of (TeO6)-O-VI and (CuO6)-O-II octahedra in every second layer giving an ABAB* stacking arrangement. Syntheses of (Cu3TeO6)-Te-II-O-IV showed that low-temperature (473 K) hydrothermal conditions generally produce the 2O polytype. XRPD measurements in combination with Raman spectroscopic analysis showed that most natural mcalpineite is the orthorhombic 2O polytype. Both XRPD and Raman spectroscopy measurements may be used to differentiate between the two polytypes of (Cu3TeO6)-Te-II-O-IV. In Raman spectroscopy, (Cu3TeO6)-Te-II-O-IV-1C has a single strong band around 730 cm(-1), whereas (Cu3TeO6)-Te-II-O-IV-2O shows a broad double maximum with bands centred around 692 and 742 cm(-1). |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000752899700003 |
Publication Date |
2022-01-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2052-5206 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.9 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 1.9 |
Call Number |
UA @ admin @ c:irua:186529 |
Serial |
6962 |
Permanent link to this record |
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Author |
Bafekry, A.; Faraji, M.; Ziabari, A.A.; Fadlallah, M.M.; Nguyen, C., V; Ghergherehchi, M.; Feghhi, S.A.H. |
Title |
A van der Waals heterostructure of MoS₂/MoSi₂N₄ : a first-principles study |
Type |
A1 Journal article |
Year |
2021 |
Publication |
New Journal Of Chemistry |
Abbreviated Journal |
New J Chem |
Volume |
45 |
Issue |
18 |
Pages |
8291-8296 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Motivated by the successful preparation of MoSi2N4 monolayers in the last year [Y.-L. Hong et al., Science, 2020, 369, 670-674], we investigate the structural, electronic and optical properties of the MoS2/MoSi2N4 heterostructure (HTS). The phonon dispersion and the binding energy calculations refer to the stability of the HTS. The heterostructure has an indirect bandgap of 1.26 (1.84) eV using PBE (HSE06) which is smaller than the corresponding value of MoSi2N4 and MoS2 monolayers. We find that the work function of the MoS2/MoSi2N4 HTS is smaller than the corresponding value of its individual monolayers. The heterostructure structure can enhance the absorption of light spectra not only in the ultraviolet region but also in the visible region as compared to MoSi2N4 and MoS2 monolayers. The refractive index behaviour of the HTS can be described as the cumulative effect which is well described in terms of a combination of the individual effects (the refractive index of MoSi2N4 and MoS2 monolayers). |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000642436200001 |
Publication Date |
2021-03-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1144-0546 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.269 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.269 |
Call Number |
UA @ admin @ c:irua:178300 |
Serial |
6964 |
Permanent link to this record |
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Author |
Bafekry, A.; Mortazavi, B.; Faraji, M.; Shahrokhi, M.; Shafique, A.; Jappor, H.R.; Nguyen, C.; Ghergherehchi, M.; Feghhi, S.A.H. |
Title |
Ab initio prediction of semiconductivity in a novel two-dimensional Sb₂X₃ (X= S, Se, Te) monolayers with orthorhombic structure |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Scientific Reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
11 |
Issue |
1 |
Pages |
10366 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Sb2S3 and Sb2Se3 are well-known layered bulk structures with weak van der Waals interactions. In this work we explore the atomic lattice, dynamical stability, electronic and optical properties of Sb2S3, Sb2Se3 and Sb2Te3 monolayers using the density functional theory simulations. Molecular dynamics and phonon dispersion results show the desirable thermal and dynamical stability of studied nanosheets. On the basis of HSE06 and PBE/GGA functionals, we show that all the considered novel monolayers are semiconductors. Using the HSE06 functional the electronic bandgap of Sb2S3, Sb2Se3 and Sb2Te3 monolayers are predicted to be 2.15, 1.35 and 1.37 eV, respectively. Optical simulations show that the first absorption coefficient peak for Sb2S3, Sb2Se3 and Sb2Te3 monolayers along in-plane polarization is suitable for the absorption of the visible and IR range of light. Interestingly, optically anisotropic character along planar directions can be desirable for polarization-sensitive photodetectors. Furthermore, we systematically investigate the electrical transport properties with combined first-principles and Boltzmann transport theory calculations. At optimal doping concentration, we found the considerable larger power factor values of 2.69, 4.91, and 5.45 for hole-doped Sb2S3, Sb2Se3, and Sb2Te3, respectively. This study highlights the bright prospect for the application of Sb2S3, Sb2Se3 and Sb2Te3 nanosheets in novel electronic, optical and energy conversion systems. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000656961400019 |
Publication Date |
2021-05-14 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 4.259 |
Call Number |
UA @ admin @ c:irua:179188 |
Serial |
6965 |
Permanent link to this record |
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Author |
Reyntjens, P.D.; Tiwari, S.; van de Put, M.L.; Sorée, B.; Vandenberghe, W.G. |
Title |
Ab-initio study of magnetically intercalated platinum diselenide : the impact of platinum vacancies |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Materials |
Abbreviated Journal |
Materials |
Volume |
14 |
Issue |
15 |
Pages |
4167 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
We study the magnetic properties of platinum diselenide (PtSe2) intercalated with Ti, V, Cr, and Mn, using first-principle density functional theory (DFT) calculations and Monte Carlo (MC) simulations. First, we present the equilibrium position of intercalants in PtSe2 obtained from the DFT calculations. Next, we present the magnetic groundstates for each of the intercalants in PtSe2 along with their critical temperature. We show that Ti intercalants result in an in-plane AFM and out-of-plane FM groundstate, whereas Mn intercalant results in in-plane FM and out-of-plane AFM. V intercalants result in an FM groundstate both in the in-plane and the out-of-plane direction, whereas Cr results in an AFM groundstate both in the in-plane and the out-of-plane direction. We find a critical temperature of <0.01 K, 111 K, 133 K, and 68 K for Ti, V, Cr, and Mn intercalants at a 7.5% intercalation, respectively. In the presence of Pt vacancies, we obtain critical temperatures of 63 K, 32 K, 221 K, and 45 K for Ti, V, Cr, and Mn-intercalated PtSe2, respectively. We show that Pt vacancies can change the magnetic groundstate as well as the critical temperature of intercalated PtSe2, suggesting that the magnetic groundstate in intercalated PtSe2 can be controlled via defect engineering. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
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Editor |
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Language |
|
Wos |
000682047700001 |
Publication Date |
2021-07-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1996-1944 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.654 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 2.654 |
Call Number |
UA @ admin @ c:irua:180540 |
Serial |
6966 |
Permanent link to this record |
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|
Author |
Hamid, I.; Jalali, H.; Peeters, F.M.; Neek-Amal, M. |
Title |
Abnormal in-plane permittivity and ferroelectricity of confined water : from sub-nanometer channels to bulk |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Journal Of Chemical Physics |
Abbreviated Journal |
J Chem Phys |
Volume |
154 |
Issue |
11 |
Pages |
114503 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Dielectric properties of nano-confined water are important in several areas of science, i.e., it is relevant in the dielectric double layer that exists in practically all heterogeneous fluid-based systems. Molecular dynamics simulations are used to predict the in-plane dielectric properties of confined water in planar channels of width ranging from sub-nanometer to bulk. Because of suppressed rotational degrees of freedom near the confining walls, the dipole of the water molecules tends to be aligned parallel to the walls, which results in a strongly enhanced in-plane dielectric constant (epsilon (parallel to)) reaching values of about 120 for channels with height 8 angstrom < h < 10 angstrom. With the increase in the width of the channel, we predict that epsilon (parallel to) decreases nonlinearly and reaches the bulk value for h > 70 angstrom. A stratified continuum model is proposed that reproduces the h > 10 angstrom dependence of epsilon (parallel to). For sub-nanometer height channels, abnormal behavior of epsilon (parallel to) is found with two orders of magnitude reduction of epsilon (parallel to) around h similar to 7.5 angstrom, which is attributed to the formation of a particular ice phase that exhibits long-time (similar to mu s) stable ferroelectricity. This is of particular importance for the understanding of the influence of confined water on the functioning of biological systems. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000629831900001 |
Publication Date |
2021-03-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-9606 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.965 |
Times cited |
13 |
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 2.965 |
Call Number |
UA @ admin @ c:irua:177579 |
Serial |
6967 |
Permanent link to this record |
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Author |
Zalalutdinov, M.K.; Robinson, J.T.; Fonseca, J.J.; LaGasse, S.W.; Pandey, T.; Lindsay, L.R.; Reinecke, T.L.; Photiadis, D.M.; Culbertson, J.C.; Cress, C.D.; Houston, B.H. |
Title |
Acoustic cavities in 2D heterostructures |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Nature Communications |
Abbreviated Journal |
Nat Commun |
Volume |
12 |
Issue |
1 |
Pages |
3267 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Two-dimensional (2D) materials offer unique opportunities in engineering the ultrafast spatiotemporal response of composite nanomechanical structures. In this work, we report on high frequency, high quality factor (Q) 2D acoustic cavities operating in the 50-600GHz frequency (f) range with f x Q up to 1 x 10(14). Monolayer steps and material interfaces expand cavity functionality, as demonstrated by building adjacent cavities that are isolated or strongly-coupled, as well as a frequency comb generator in MoS2/h-BN systems. Energy dissipation measurements in 2D cavities are compared with attenuation derived from phonon-phonon scattering rates calculated using a fully microscopic ab initio approach. Phonon lifetime calculations extended to low frequencies (<1THz) and combined with sound propagation analysis in ultrathin plates provide a framework for designing acoustic cavities that approach their fundamental performance limit. These results provide a pathway for developing platforms employing phonon-based signal processing and for exploring the quantum nature of phonons. Here, authors report on acoustic cavities in 2D materials operating in the 50-600GHz range and show that quality factors approach the limit set by lattice anharmonicity. Functionality expanded by heterogeneities (steps and interfaces) is demonstrated through coupled cavities and frequency comb generation. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000660772400004 |
Publication Date |
2021-06-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 12.124 |
Call Number |
UA @ admin @ c:irua:179597 |
Serial |
6968 |
Permanent link to this record |
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Author |
Akgenc, B.; Sarikurt, S.; Yagmurcukardes, M.; Ersan, F. |
Title |
Aluminum and lithium sulfur batteries : a review of recent progress and future directions |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Journal Of Physics-Condensed Matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
33 |
Issue |
25 |
Pages |
253002 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Advanced materials with various micro-/nanostructures have attracted plenty of attention for decades in energy storage devices such as rechargeable batteries (ion- or sulfur based batteries) and supercapacitors. To improve the electrochemical performance of batteries, it is uttermost important to develop advanced electrode materials. Moreover, the cathode material is also important that it restricts the efficiency and practical application of aluminum-ion batteries. Among the potential cathode materials, sulfur has become an important candidate material for aluminum-ion batteries cause of its considerable specific capacity. Two-dimensional materials are currently potential candidates as electrodes from lab-scale experiments to possible pragmatic theoretical studies. In this review, the fundamental principles, historical progress, latest developments, and major problems in Li-S and Al-S batteries are reviewed. Finally, future directions in terms of the experimental and theoretical applications have prospected. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000655281200001 |
Publication Date |
2021-04-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 2.649 |
Call Number |
UA @ admin @ c:irua:179034 |
Serial |
6971 |
Permanent link to this record |
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|
Author |
Cunha, S.M.; de Costa, D.R.; Pereira Jr, J.M.; Costa Filho, R.N.; Van Duppen, B.; Peeters, F.M. |
Title |
Band-gap formation and morphing in alpha-T-3 superlattices |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
104 |
Issue |
11 |
Pages |
115409 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Electrons in alpha-T-3 lattices behave as condensed-matter analogies of integer-spin Dirac fermions. The three atoms making up the unit cell bestow the energy spectrum with an additional energy band that is completely flat, providing unique electronic properties. The interatomic hopping term, alpha, is known to strongly affect the electronic spectrum of the two-dimensional (2D) lattice, allowing it to continuously morph from graphenelike responses to the behavior of fermions in a dice lattice. For pristine lattice structures the energy bands are gapless, but small deviations in the atomic equivalence of the three sublattices will introduce gaps in the spectrum. It is unknown how these affect transport and electronic properties such as the energy spectrum of superlattice minibands. Here we investigate the dependency of these properties on the parameter a accounting for different symmetry-breaking terms, and we show how it affects band-gap formation. Furthermore, we find that superlattices can force band gaps to close and shift in energy. Our results demonstrate that alpha-T-3 superlattices provide a versatile material for 2D band-gap engineering purposes. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000696091600003 |
Publication Date |
2021-09-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ admin @ c:irua:181544 |
Serial |
6972 |
Permanent link to this record |
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Author |
Tiwari, S.; Vanherck, J.; Van de Put, M.L.; Vandenberghe, W.G.; Sorée, B. |
Title |
Computing Curie temperature of two-dimensional ferromagnets in the presence of exchange anisotropy |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Physical review research |
Abbreviated Journal |
|
Volume |
3 |
Issue |
4 |
Pages |
043024 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We compare three first-principles methods of calculating the Curie temperature in two-dimensional (2D) ferromagnetic materials (FM), modeled using the Heisenberg model, and propose a simple formula for estimating the Curie temperature with high accuracy that works for all common 2D lattice types. First, we study the effect of exchange anisotropy on the Curie temperature calculated using the Monte Carlo (MC), the Green's function, and the renormalized spin-wave (RNSW) methods. We find that the Green's function method overestimates the Curie temperature in high-anisotropy regimes compared to the MC method, whereas the RNSW method underestimates the Curie temperature compared to the MC and the Green's function methods. Next, we propose a closed-form formula for calculating the Curie temperature of 2D FMs, which provides an estimate of the Curie temperature that is greatly improved over the mean-field expression for magnetic material screening. We apply the closed-form formula to predict the Curie temperature 2D magnets screened from the C2DB database and discover several high Curie temperature FMs, with Fe2F2 and MoI2 emerging as the most promising 2D ferromagnets. Finally, by comparing to experimental results for CrI3, CrCl3, and CrBr3, we conclude that for small effective anisotropies, the Green's-function-based equations are preferable, while for larger anisotropies, MC-based results are more predictive. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000707506500001 |
Publication Date |
2021-10-11 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:182522 |
Serial |
6975 |
Permanent link to this record |
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Author |
Bafekry, A.; Stampfl, C.; Naseri, M.; Fadlallah, M.M.; Faraji, M.; Ghergherehchi, M.; Gogova, D.; Feghhi, S.A.H. |
Title |
Effect of electric field and vertical strain on the electro-optical properties of the MoSi2N4 bilayer : a first-principles calculation |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Journal Of Applied Physics |
Abbreviated Journal |
J Appl Phys |
Volume |
129 |
Issue |
15 |
Pages |
155103 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Recently, a two-dimensional (2D) MoSi 2N 4 (MSN) structure has been successfully synthesized [Hong et al., Science 369(6504), 670-674 (2020)]. Motivated by this result, we investigate the structural, electronic, and optical properties of MSN monolayer (MSN-1L) and bilayer (MSN-2L) under the applied electric field (E-field) and strain using density functional theory calculations. We find that the MSN-2L is a semiconductor with an indirect bandgap of 1.60 (1.80)eV using Perdew-Burke-Ernzerhof (HSE06). The bandgap of MSN-2L decreases as the E-field increases from 0.1 to 0.6V/angstrom and for larger E-field up to 1.0V/angstrom the bilayer becomes metallic. As the vertical strain increases, the bandgap decreases; more interestingly, a semiconductor to a metal phase transition is observed at a strain of 12 %. Furthermore, the optical response of the MSN-2L is in the ultraviolet (UV) region of the electromagnetic spectrum. The absorption edge exhibits a blue shift by applying an E-field or a vertical compressive strain. The obtained interesting properties suggest MSN-2L as a promising material in electro-mechanical and UV opto-mechanical devices. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000640620400003 |
Publication Date |
2021-04-15 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 2.068 |
Call Number |
UA @ admin @ c:irua:178233 |
Serial |
6981 |
Permanent link to this record |
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Author |
Conti, S.; Perali, A.; Peeters, F.M.; Neilson, D. |
Title |
Effect of mismatched electron-hole effective masses on superfluidity in double layer solid-state systems |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Condensed Matter |
Abbreviated Journal |
|
Volume |
6 |
Issue |
2 |
Pages |
14 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Superfluidity has been predicted and now observed in a number of different electron-hole double-layer semiconductor heterostructures. In some of the heterostructures, such as GaAs and Ge-Si electron-hole double quantum wells, there is a strong mismatch between the electron and hole effective masses. We systematically investigate the sensitivity to unequal masses of the superfluid properties and the self-consistent screening of the electron-hole pairing interaction. We find that the superfluid properties are insensitive to mass imbalance in the low density BEC regime of strongly-coupled boson-like electron-hole pairs. At higher densities, in the BEC-BCS crossover regime of fermionic pairs, we find that mass imbalance between electrons and holes weakens the superfluidity and expands the density range for the BEC-BCS crossover regime. This permits screening to kill the superfluid at a lower density than for equal masses. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000665155800001 |
Publication Date |
2021-04-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2410-3896 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
1 |
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:179635 |
Serial |
6982 |
Permanent link to this record |
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Author |
Rzeszotarski, B.; Mrenca-Kolasinska, A.; Peeters, F.M.; Szafran, B. |
Title |
Effective Landé factors for an electrostatically defined quantum point contact in silicene |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Scientific Reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
11 |
Issue |
1 |
Pages |
19892 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
The transconductance and effective Lande g* factors for a quantum point contact defined in silicene by the electric field of a split gate is investigated. The strong spin-orbit coupling in buckled silicene reduces the g* factor for in-plane magnetic field from the nominal value 2 to around 1.2 for the first-to 0.45 for the third conduction subband. However, for perpendicular magnetic field we observe an enhancement of g* factors for the first subband to 5.8 in nanoribbon with zigzag and to 2.5 with armchair edge. The main contribution to the Zeeman splitting comes from the intrinsic spin-orbit coupling defined by the Kane-Mele form of interaction. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000706380800089 |
Publication Date |
2021-10-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2045-2322 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
4.259 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 4.259 |
Call Number |
UA @ admin @ c:irua:182502 |
Serial |
6983 |
Permanent link to this record |
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Author |
Conti, S.; Saberi-Pouya, S.; Perali, A.; Virgilio, M.; Peeters, F.M.; Hamilton, A.R.; Scappucci, G.; Neilson, D. |
Title |
Electron-hole superfluidity in strained Si/Ge type II heterojunctions |
Type |
A1 Journal article |
Year |
2021 |
Publication |
npj Quantum Materials |
Abbreviated Journal |
|
Volume |
6 |
Issue |
1 |
Pages |
41 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Excitons are promising candidates for generating superfluidity and Bose-Einstein condensation (BEC) in solid-state devices, but an enabling material platform with in-built band structure advantages and scaling compatibility with industrial semiconductor technology is lacking. Here we predict that spatially indirect excitons in a lattice-matched strained Si/Ge bilayer embedded into a germanium-rich SiGe crystal would lead to observable mass-imbalanced electron-hole superfluidity and BEC. Holes would be confined in a compressively strained Ge quantum well and electrons in a lattice-matched tensile strained Si quantum well. We envision a device architecture that does not require an insulating barrier at the Si/Ge interface, since this interface offers a type II band alignment. Thus the electrons and holes can be kept very close but strictly separate, strengthening the electron-hole pairing attraction while preventing fast electron-hole recombination. The band alignment also allows a one-step procedure for making independent contacts to the electron and hole layers, overcoming a significant obstacle to device fabrication. We predict superfluidity at experimentally accessible temperatures of a few Kelvin and carrier densities up to similar to 6 x 10(10) cm(-2), while the large imbalance of the electron and hole effective masses can lead to exotic superfluid phases. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000642904200001 |
Publication Date |
2021-04-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2397-4648 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
9 |
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:178226 |
Serial |
6984 |
Permanent link to this record |
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Author |
Bafekry, A.; Sarsari, I.A.; Faraji, M.; Fadlallah, M.M.; Jappor, H.R.; Karbasizadeh, S.; Nguyen, V.; Ghergherehchi, M. |
Title |
Electronic and magnetic properties of two-dimensional of FeX (X = S, Se, Te) monolayers crystallize in the orthorhombic structures |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
118 |
Issue |
14 |
Pages |
143102 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In this Letter, we explore the lattice, dynamical stability, and electronic and magnetic properties of FeTe bulk and FeX (X=S, Se, Te) monolayers using the density functional calculations. The phonon dispersion relation, elastic stability criteria, and cohesive energy results show the stability of studied FeX monolayers. The mechanical properties reveal that all FeX monolayers have a brittle nature. Furthermore, these structures are stable as we move down the 6A group in the periodic table, i.e., from S, Se, and Te. The stability and work function decrease as the electronegativity decreases. The spin-polarized electronic structures demonstrate that the FeTe monolayer has a total magnetization of 3.8 mu (B), which is smaller than the magnetization of FeTe bulk (4.7 mu (B)). However, FeSe and FeS are nonmagnetic monolayers. The FeTe monolayer can be a good candidate material for spin filter applications due to its electronic and magnetic properties. This study highlights the bright prospect for the application of FeX monolayers in electronic structures. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000637703700001 |
Publication Date |
2021-04-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-6951; 1077-3118 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 3.411 |
Call Number |
UA @ admin @ c:irua:177731 |
Serial |
6985 |
Permanent link to this record |
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Author |
Bafekry, A.; Gogova, D.; M. Fadlallah, M.; V. Chuong, N.; Ghergherehchi, M.; Faraji, M.; Feghhi, S.A.H.; Oskoeian, M. |
Title |
Electronic and optical properties of two-dimensional heterostructures and heterojunctions between doped-graphene and C- and N-containing materials |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Physical Chemistry Chemical Physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
23 |
Issue |
8 |
Pages |
4865-4873 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The electronic and optical properties of vertical heterostructures (HTSs) and lateral heterojunctions (HTJs) between (B,N)-codoped graphene (dop@Gr) and graphene (Gr), C3N, BC3 and h-BN monolayers are investigated using van der Waals density functional theory calculations. We have found that all the considered HTSs are energetically and thermally feasible at room temperature, and therefore they can be synthesized experimentally. The dop@Gr/Gr, BC3/dop@Gr and BN/dop@Gr HTSs are semiconductors with direct bandgaps of 0.1 eV, 80 meV and 1.23 eV, respectively, while the C3N/dop@Gr is a metal because of the strong interaction between dop@Gr and C3N layers. On the other hand, the dop@Gr-Gr and BN-dop@Gr HTJs are semiconductors, whereas the C3N-dop@Gr and BC3-dop@Gr HTJs are metals. The proposed HTSs can enhance the absorption of light in the whole wavelength range as compared to Gr and BN monolayers. The applied electric field or pressure strain changes the bandgaps of the HTSs and HTJs, indicating that these HTSs are highly promising for application in nanoscale multifunctional devices. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000625306100038 |
Publication Date |
2021-02-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076; 1463-9084 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 4.123 |
Call Number |
UA @ admin @ c:irua:177659 |
Serial |
6986 |
Permanent link to this record |
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Author |
Pinto, N.; McNaughton, B.; Minicucci, M.; Milošević, M.V.; Perali, A. |
Title |
Electronic transport mechanisms correlated to structural properties of a reduced graphene oxide sponge |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Nanomaterials |
Abbreviated Journal |
Nanomaterials-Basel |
Volume |
11 |
Issue |
10 |
Pages |
2503 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
We report morpho-structural properties and charge conduction mechanisms of a foamy “graphene sponge ”, having a density as low as & AP;0.07 kg/m3 and a carbon to oxygen ratio C:O & SIME; 13:1. The spongy texture analysed by scanning electron microscopy is made of irregularly-shaped millimetres-sized small flakes, containing small crystallites with a typical size of & SIME;16.3 nm. A defect density as high as & SIME;2.6 x 1011 cm-2 has been estimated by the Raman intensity of D and G peaks, dominating the spectrum from room temperature down to & SIME;153 K. Despite the high C:O ratio, the graphene sponge exhibits an insulating electrical behavior, with a raise of the resistance value at & SIME;6 K up to 5 orders of magnitude with respect to the room temperature value. A variable range hopping (VRH) conduction, with a strong 2D character, dominates the charge carriers transport, from 300 K down to 20 K. At T < 20 K, graphene sponge resistance tends to saturate, suggesting a temperature-independent quantum tunnelling. The 2D-VRH conduction originates from structural disorder and is consistent with hopping of charge carriers between sp2 defects in the plane, where sp3 clusters related to oxygen functional groups act as potential barriers.</p> |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000713174500001 |
Publication Date |
2021-09-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2079-4991 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
3.553 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 3.553 |
Call Number |
UA @ admin @ c:irua:184050 |
Serial |
6988 |
Permanent link to this record |
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Author |
Sun, P.Z.; Yagmurcukardes, M.; Zhang, R.; Kuang, W.J.; Lozada-Hidalgo, M.; Liu, B.L.; Cheng, H.-M.; Wang, F.C.; Peeters, F.M.; Grigorieva, I.V.; Geim, A.K. |
Title |
Exponentially selective molecular sieving through angstrom pores |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Nature Communications |
Abbreviated Journal |
Nat Commun |
Volume |
12 |
Issue |
1 |
Pages |
7170 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Two-dimensional crystals with angstrom-scale pores are widely considered as candidates for a next generation of molecular separation technologies aiming to provide extreme, exponentially large selectivity combined with high flow rates. No such pores have been demonstrated experimentally. Here we study gas transport through individual graphene pores created by low intensity exposure to low kV electrons. Helium and hydrogen permeate easily through these pores whereas larger species such as xenon and methane are practically blocked. Permeating gases experience activation barriers that increase quadratically with molecules' kinetic diameter, and the effective diameter of the created pores is estimated as similar to 2 angstroms, about one missing carbon ring. Our work reveals stringent conditions for achieving the long sought-after exponential selectivity using porous two-dimensional membranes and suggests limits on their possible performance. Two-dimensional membranes with angstrom-sized pores are predicted to combine high permeability with exceptional selectivity, but experimental demonstration has been challenging. Here the authors realize angstrom-sized pores in monolayer graphene and demonstrate gas transport with activation barriers increasing quadratically with the molecular kinetic diameter. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000728562700016 |
Publication Date |
2021-12-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2041-1723 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
28 |
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 12.124 |
Call Number |
UA @ admin @ c:irua:184840 |
Serial |
6989 |
Permanent link to this record |