Home | [1–100] << 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 >> [201–249] |
Records | |||||
---|---|---|---|---|---|
Author | Li, Y.; Zhang, X.; Shen, L.; Luo, J.; Tao, X.; Liu, F.; Xu, G.; Wang, Y.; Geise, H.J.; Van Tendeloo, G. | ||||
Title | Controlling the diameters in large-scale synthesis of single-walled carbon nanotubes by catalytic decomposition of CH4 | Type | A1 Journal article | ||
Year | 2004 | Publication | Chemical physics letters | Abbreviated Journal | Chem Phys Lett |
Volume | 398 | Issue | 1-3 | Pages | 276-282 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | High-quality single-walled carbon nanotubes (SWNTs) are synthesized in gram amount on Fe-Mo/MgO catalysts by catalytic decomposition of CH4 in H-2 or N-2. Raman data reveal that the as-prepared SATNTs have a diameter of about 0.74-1.29 nm. It is found that the diameter of the as-prepared SWNTs can be controlled mainly by adjusting the molar ratio of Fe-Mo versus the MgO support. Several other factors that potentially influence the growth of SWNTs have been studied in detail. The experimental results show that the nature of the catalyst determines the diameter of the as-prepared SWNTs. (C) 2004 Elsevier B.V. All rights reserved. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000224720300050 | Publication Date | 2004-10-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0009-2614; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.815 | Times cited | 45 | Open Access | |
Notes | Approved | Most recent IF: 1.815; 2004 IF: 2.438 | |||
Call Number | UA @ lucian @ c:irua:103720 | Serial | 507 | ||
Permanent link to this record | |||||
Author | Li, Y.; Zhang, X.; Geise, H.J.; Van Tendeloo, G. | ||||
Title | Behavior of Ni-doped MgMoO4 single-phase catalysts for synthesis of multiwalled carbon nanotube bundles | Type | A1 Journal article | ||
Year | 2007 | Publication | Chemical vapor deposition | Abbreviated Journal | Chem Vapor Depos |
Volume | 13 | Issue | 1 | Pages | 30-36 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | |||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Weinheim | Editor | ||
Language | Wos | 000244062200005 | Publication Date | 2007-01-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0948-1907;1521-3862; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.333 | Times cited | 4 | Open Access | |
Notes | Approved | Most recent IF: 1.333; 2007 IF: 1.936 | |||
Call Number | UA @ lucian @ c:irua:63787 | Serial | 225 | ||
Permanent link to this record | |||||
Author | Li, Y.; Yang, X.-Y.; Tian, G.; Vantomme, A.; Yu, J.; Van Tendeloo, G.; Su, B.-L. | ||||
Title | Chemistry of trimethyl aluminum: a spontaneous route to thermally stable 3D crystalline macroporous alumina foams with a hierarchy of pore sizes | Type | A1 Journal article | ||
Year | 2010 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 22 | Issue | 10 | Pages | 3251-3258 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A simple and spontaneous one-pot self-formation procedure that is easy to scale up has been developed based on the chemistry of trimethylaluminum (TMA), leading to thermally stable macroporous crystalline alumina with a very unique and unprecedented three-dimensional (3D) hierarchical pore structure consisting of well-defined wormlike mesopores. TMA is the precursor of both product and porogene (viz, two working functions within the same molecule (2 in 1)). The materials obtained have been intensively characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), N2 adsorption−desorption, and mercury porosimetry. The open cagelike macrocavities are self-constructed by mesoporous nanorods (diameter of ca. 40−70 nm), which are themselves formed by a random assembly of fibrous nanoparticles 5−6 nm in size. Optical microscopy (OM) has been used in situ to follow the synthesis procedure, which led to the proposal of the formation mechanism. Methane molecules as porogens, which were instantaneously released because of the fast hydrolysis of the chemical precursor, were the key factor in producing these 3D structures with uniform co-continuous macropores that interconnected directly with the wormlike mesopores. The important characteristic of this procedure is the concurrent formation of a multiscaled porous network. The material exhibits great thermal stability. The hierarchically mesoporous−macroporous Al2O3 obtained is quite attractive for a myriad of applications, from catalysis to biomedicine. The present work illustrates that the one-pot self-formation concept, based on the chemistry of alkyl metals, is a versatile method to design industrially valuable hierarchically porous materials. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000277635000030 | Publication Date | 2010-04-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0897-4756;1520-5002; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 38 | Open Access | |
Notes | Approved | Most recent IF: 9.466; 2010 IF: 6.400 | |||
Call Number | UA @ lucian @ c:irua:82760 | Serial | 356 | ||
Permanent link to this record | |||||
Author | Li, Y.; Yang, X.-Y.; Rooke, J.; Van Tendeloo, G.; Su, B.-L. | ||||
Title | Ultralong Cu(OH)(2) and CuO nanowire bundles: PEG200-directed crystal growth for enhanced photocatalytic performance | Type | A1 Journal article | ||
Year | 2010 | Publication | Journal of colloid and interface science | Abbreviated Journal | J Colloid Interf Sci |
Volume | 348 | Issue | 2 | Pages | 303-312 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Ultralong Cu(OH)(2) and CuO nanowire bundles with lengths ranging from tens to hundreds of micrometers have been selectively synthesized on a large scale by a facile solution-phase method, using PEG200 as growth-directing agent. The growth mechanisms were investigated by monitoring the nanowire evolution process. The results showed that under the action of PEG200 molecules, the Cu(OH)(2) and CuO nanowires were first formed through oriented attachment of colloidal particles, then through side self-assembly leading to nanowire bundles, and finally to CuO nanoleaves. PEG200 plays a critical role in the synthesis of nanowires as it not only prevents the random aggregation of colloidal particles toward CuO nanoleaves but also helps to orientate nanowire growth by the coalescence and alignment in one direction of the colloidal particles. The concentration of OH(-) in the reaction system is also important for nanowire growth. In the absence of PEG200, nanoleaves are formed by an Ostwald ripening process. The band-gap value estimated from a UV-Vis absorption spectrum of CuO nanowire bundles is 2.32 eV. The photodegradation of a model pollutant, rhodamine B, by CuO nanowires and nanoleaves was compared with commercial nanopowders, showing that the as-synthesized ultralong CuO polycrystalline nanowire bundles have an enhanced photocatalytic activity with 87% decomposition of rhodamine B after an 8-h reaction, which was much higher than that of single-crystal nanoleaves (61%) and commercial nanopowders (32%). The origin of the high photocatalytic activity of these new polycrystalline CuO nanowire bundles has been discussed. This present work reveals that the (0 0 2) crystallographic surface is more favorable for photocatalytic decomposition of organic compounds and that these ultralong CuO nanowire bundles are potential candidates for photocatalysts in wastewater treatment. (C) 2010 Elsevier Inc. All rights reserved. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000279968700002 | Publication Date | 2010-04-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-9797; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.233 | Times cited | 70 | Open Access | |
Notes | Approved | Most recent IF: 4.233; 2010 IF: 3.068 | |||
Call Number | UA @ lucian @ c:irua:95589 | Serial | 3795 | ||
Permanent link to this record | |||||
Author | Li, Y.; Tan, H.; Yang, X.-Y.; Goris, B.; Verbeeck, J.; Bals, S.; Colson, P.; Cloots, R.; Van Tendeloo, G.; Su, B.-L. | ||||
Title | Well shaped Mn3O4 nano-octahedra with anomalous magnetic behavior and enhanced photodecomposition properties | Type | A1 Journal article | ||
Year | 2011 | Publication | Small | Abbreviated Journal | Small |
Volume | 7 | Issue | 4 | Pages | 475-483 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Very uniform and well shaped Mn3O4 nano-octahedra are synthesized using a simple hydrothermal method under the help of polyethylene glycol (PEG200) as a reductant and shape-directing agent. The nano-octahedra formation mechanism is monitored. The shape and crystal orientation of the nanoparticles is reconstructed by scanning electron microscopy and electron tomography, which reveals that the nano-octahedra only selectively expose {101} facets at the external surfaces. The magnetic testing demonstrates that the Mn3O4 nano-octahedra exhibit anomalous magnetic properties: the Mn3O4 nano-octahedra around 150 nm show a similar Curie temperature and blocking temperature to Mn3O4 nanoparticles with 10 nm size because of the vertical axis of [001] plane and the exposed {101} facets. With these Mn3O4 nano-octahedra as a catalyst, the photodecomposition of rhodamine B is evaluated and it is found that the photodecomposition activity of Mn3O4 nano-octahedra is much superior to that of commercial Mn3O4 powders. The anomalous magnetic properties and high superior photodecomposition activity of well shaped Mn3O4 nano-octahedra should be related to the special shape of the nanoparticles and the abundantly exposed {101} facets at the external surfaces. Therefore, the shape preference can largely broaden the application of the Mn3O4 nano-octahedra. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Weinheim | Editor | ||
Language | Wos | 000288080400008 | Publication Date | 2011-01-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1613-6810; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.643 | Times cited | 131 | Open Access | |
Notes | This work was realized in the frame of an Interuniversity Attraction Poles Program (Inanomat-P6/17)-Belgian State-Belgian Science Policy and the project “Redugaz”, financially supported by the European community and the Wallon government in the frame of Interreg IV (France-Wallonie). B. L. S. acknowledges the Chinese Central Government for an “Expert of the State” position in the program of “Thousand talents” and the Chinese Ministry of Education for a Changjiang Scholar position at the Wuhan University of Technology. H. T. acknowledges the financial support from FWO-Vlaanderen (Project nr. G.0147.06). J.V. thanks the financial support from the European Union under Framework 6 program for Integrated Infrastructure Initiative, Reference 026019 ESTEEM. | Approved | Most recent IF: 8.643; 2011 IF: 8.349 | ||
Call Number | UA @ lucian @ c:irua:87908 | Serial | 3914 | ||
Permanent link to this record | |||||
Author | Li, Y.; Tan, H.; Lebedev, O.; Verbeeck, J.; Biermans, E.; Van Tendeloo, G.; Su, B.-L. | ||||
Title | Insight into the growth of multiple branched MnOOH nanorods | Type | A1 Journal article | ||
Year | 2010 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
Volume | 10 | Issue | 7 | Pages | 2969-2976 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Multiple branched manganese oxide hydroxide (MnOOH) nanorods prepared by a hydrothermal process were extensively studied by transmission electron microscopy (TEM). A model of the branch formation is proposed together with a study of the interface structure. The sword-like tip plays a crucial role for the nanorods to form different shapes. Importantly, the branching occurs at an angle of around either 57 degrees or 123 degrees. Specifically, a (111) twin plane can only be formed at the interface with a 123 degrees angle. The interfaces formed with a 57 degrees angle usually contain edge dislocations. Electron energy loss spectroscopy (EELS) demonstrates that the whole crystal has a uniform chemical composition. Interestingly, an epitaxial growth of Mn3O4 at the radial surface was also observed under electron beam irradiation; this is because of the rough purification of the products. The proposed mechanism is expected to shed light on the branched/dendrite nanostructure growth and to provide opportunities for further novel nanomaterial structure growth and design. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000279422700027 | Publication Date | 2010-06-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1528-7483;1528-7505; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.055 | Times cited | 41 | Open Access | |
Notes | Fwo; Esteem 026019 | Approved | Most recent IF: 4.055; 2010 IF: 4.390 | ||
Call Number | UA @ lucian @ c:irua:83886UA @ admin @ c:irua:83886 | Serial | 1672 | ||
Permanent link to this record | |||||
Author | Li, Y.; Quinn, B.K.; Niinemets, Ü.; Schrader, J.; Gielis, J.; Liu, M.; Shi, P. | ||||
Title | Ellipticalness index : a simple measure of the complexity of oval leaf shape | Type | A1 Journal article | ||
Year | 2022 | Publication | Pakistan journal of botany : An official publication of pakistan botanical society | Abbreviated Journal | Pak J Bot |
Volume | 54 | Issue | 6 | Pages | 1-8 |
Keywords | A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | Plants have diverse leaf shapes that have evolved to adapt to the environments they have experienced over their evolutionary history. Leaf shape and leaf size can greatly influence the growth rate, competitive ability, and productivity of plants. However, researchers have long struggled to decide how to properly quantify the complexity of leaf shape. Prior studies recommended the leaf roundness index (RI = 4πA/P2) or dissection index (DI = ), where P is leaf perimeter and A is leaf area. However, these two indices merely measure the extent of the deviation of leaf shape from a circle, which is usually invalid as leaves are seldom circular. In this study, we proposed a simple measure, named the ellipticalness index (EI), for quantifying the complexity of leaf shape based on the hypothesis that the shape of any oval leaf can be regarded as a variation from a standard ellipse. 2220 leaves from nine species of Magnoliaceae were sampled to check the validity of the EI. We also tested the validity of the Montgomery equation (ME), which assumes a proportional relationship between leaf area and the product of leaf length and width, because the EI actually comes from the proportionality coefficient of the ME. We also compared the ME with five other models of leaf area. The ME was found to be the best model for calculating leaf area based on consideration of the trade-off between model fit vs. complexity, which strongly supported the robustness of the EI for describing oval leaf shape. The new index can account for both leaf shape and size, and we conclude that it is a promising method for quantifying and comparing oval leaf shapes across species in future studies. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000814279700028 | Publication Date | 2022-05-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0556-3321 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.2 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 1.2 | |||
Call Number | UA @ admin @ c:irua:188469 | Serial | 7153 | ||
Permanent link to this record | |||||
Author | Li, Y.; Quinn, B.K.; Gielis, J.; Li, Y.; Shi, P. | ||||
Title | Evidence that supertriangles exist in nature from the vertical projections of Koelreuteria paniculata fruit | Type | A1 Journal article | ||
Year | 2022 | Publication | Symmetry | Abbreviated Journal | Symmetry-Basel |
Volume | 14 | Issue | 1 | Pages | 23 |
Keywords | A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | Many natural radial symmetrical shapes (e.g., sea stars) follow the Gielis equation (GE) or its twin equation (TGE). A supertriangle (three triangles arranged around a central polygon) represents such a shape, but no study has tested whether natural shapes can be represented as/are supertriangles or whether the GE or TGE can describe their shape. We collected 100 pieces of Koelreuteria paniculata fruit, which have a supertriangular shape, extracted the boundary coordinates for their vertical projections, and then fitted them with the GE and TGE. The adjusted root mean square errors (RMSEadj) of the two equations were always less than 0.08, and >70% were less than 0.05. For 57/100 fruit projections, the GE had a lower RMSEadj than the TGE, although overall differences in the goodness of fit were non-significant. However, the TGE produces more symmetrical shapes than the GE as the two parameters controlling the extent of symmetry in it are approximately equal. This work demonstrates that natural supertriangles exist, validates the use of the GE and TGE to model their shapes, and suggests that different complex radially symmetrical shapes can be generated by the same equation, implying that different types of biological symmetry may result from the same biophysical mechanisms. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000746030100001 | Publication Date | 2021-12-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2073-8994 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.7 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 2.7 | |||
Call Number | UA @ admin @ c:irua:186453 | Serial | 7158 | ||
Permanent link to this record | |||||
Author | Li, Y.; Niklas, K.J.; Gielis, J.; Niinemets, Ü.; Schrader, J.; Wang, R.; Shi, P. | ||||
Title | An elliptical blade is not a true ellipse, but a superellipse : evidence from two Michelia species | Type | A1 Journal article | ||
Year | 2022 | Publication | Journal of forestry research | Abbreviated Journal | J Forestry Res |
Volume | 33 | Issue | 4 | Pages | 1341-1348 |
Keywords | A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | The shape of leaf laminae exhibits considerable diversity and complexity that reflects adaptations to environmental factors such as ambient light and precipitation as well as phyletic legacy. Many leaves appear to be elliptical which may represent a ‘default’ developmental condition. However, whether their geometry truly conforms to the ellipse equation (EE), i.e., (x/a)2 + (y/b)2 = 1, remains conjectural. One alternative is described by the superellipse equation (SE), a generalized version of EE, i.e., |x/a|n +|y/b|n = 1. To test the efficacy of EE versus SE to describe leaf geometry, the leaf shapes of two Michelia species (i.e., M. cavaleriei var. platypetala, and M. maudiae), were investigated using 60 leaves from each species. Analysis shows that the majority of leaves (118 out of 120) had adjusted root-mean-square errors of < 0.05 for the nonlinear fitting of SE to leaf geometry, i.e., the mean absolute deviation from the polar point to leaf marginal points was smaller than 5% of the radius of a hypothesized circle with its area equaling leaf area. The estimates of n for the two species were ˂ 2, indicating that all sampled leaves conformed to SE and not to EE. This study confirms the existence of SE in leaves, linking this to its potential functional advantages, particularly the possible influence of leaf shape on hydraulic conductance. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000695118600001 | Publication Date | 2021-09-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1007-662x; 1993-0607 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 3 | |||
Call Number | UA @ admin @ c:irua:180967 | Serial | 7152 | ||
Permanent link to this record | |||||
Author | Li, X.Q.; Peeters, F.M.; Geim, A.K. | ||||
Title | The Hall effect of an inhomogeneous magnetic field in mesoscopic structures | Type | A1 Journal article | ||
Year | 1997 | Publication | Journal of physics : condensed matter | Abbreviated Journal | J Phys-Condens Mat |
Volume | 9 | Issue | Pages | 8065-8073 | |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | |||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | London | Editor | ||
Language | Wos | A1997XY64300012 | Publication Date | 0000-00-00 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0953-8984 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.649 | Times cited | 8 | Open Access | |
Notes | Approved | Most recent IF: 2.649; 1997 IF: 1.479 | |||
Call Number | UA @ lucian @ c:irua:19290 | Serial | 1401 | ||
Permanent link to this record | |||||
Author | Li, X.Q.; Peeters, F.M. | ||||
Title | Scattering on circular inhomogeneous magnetic field profiles in an electron waveguide junction | Type | A1 Journal article | ||
Year | 1997 | Publication | Superlattices and microstructures | Abbreviated Journal | Superlattice Microst |
Volume | 22 | Issue | Pages | 243-249 | |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | |||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | London | Editor | ||
Language | Wos | A1997XV53900017 | Publication Date | 0000-00-00 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0749-6036 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.123 | Times cited | 9 | Open Access | |
Notes | Approved | Most recent IF: 2.123; 1997 IF: 0.694 | |||
Call Number | UA @ lucian @ c:irua:19302 | Serial | 2952 | ||
Permanent link to this record | |||||
Author | Li, W.; Tong, W.; Yadav, A.; Bladt, E.; Bals, S.; Funston, A.M.; Etheridge, J. | ||||
Title | Shape control beyond the seeds in gold nanoparticles | Type | A1 Journal article | ||
Year | 2021 | Publication | Chemistry Of Materials | Abbreviated Journal | Chem Mater |
Volume | 33 | Issue | 23 | Pages | 9152-9164 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | In typical seed-mediated syntheses of metal nanocrystals, the shape of the nanocrystal is determined largely by the seed nucleation environment and subsequent growth environment (where “environment” refers to the chemical environment, including the surfactant and additives). In this approach, crystallinity is typically determined by the seeds, and surfaces are controlled by the environment(s). However, surface energies, and crystallinity, are both influenced by the choice of environment(s). This limits the permutations of crystallinity and surface facets that can be mixed and matched to generate new nanocrystal morphologies. Here, we control post-seed growth to deliberately incorporate twin planes during the growth stage to deliver new final morphologies, including twinned cubes and bipyramids from single-crystal seeds. The nature and number of twin planes, together with surfactant control of facet growth, define the final nanoparticle morphology. Moreover, by breaking symmetry, the twin planes introduce new facet orientations. This additional mechanism opens new routes for the synthesis of different morphologies and facet orientations. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000753956100012 | Publication Date | 0000-00-00 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0897-4756; 1520-5002 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 3 | Open Access | Not_Open_Access |
Notes | This work was supported by the Australian Research Council (ARC) Grants DP160104679 and CE170100026 and used microscopes at the Monash Centre for Electron Microscopy funded by ARC Grants LE0454166, LE110100223, and LE140100104. W.L. thanks the support of the Australian Government Research Training Program (RTP) scholarship. W.T. thanks the Australian Department of Education and Monash University for the IPRS and APA scholarships. E.B. acknowledges financial support and a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). The authors thank Dr. Matthew Weyland and Dr. Tim Peterson for helpful discussions. A.Y. thanks the support from Post Graduation Publication Award (PPA) scholarship from Monash University. | Approved | Most recent IF: 9.466 | ||
Call Number | UA @ admin @ c:irua:187229 | Serial | 7065 | ||
Permanent link to this record | |||||
Author | Li, W.; Hu, Z.-Y.; Zhang, Z.; Wei, P.; Zhang, J.; Pu, Z.; Zhu, J.; He, D.; Mu, S.; Van Tendeloo, G. | ||||
Title | Nano-single crystal coalesced PtCu nanospheres as robust bifunctional catalyst for hydrogen evolution and oxygen reduction reactions | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of catalysis | Abbreviated Journal | J Catal |
Volume | 375 | Issue | 375 | Pages | 164-170 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Because of high electrocatalytic activity, Pt based metal nanospheres (NSs) have attracted a lot of attention. Hence, multi-particle nano-single crystal coalesced PtCu NSs are designed and successfully synthesized by a cost-effective aqueous solution method. The formed PtCu NS catalyst exhibits a superior hydrogen evolution reaction (HER) electrocatalytic activity with an ultralow onset potential of 18 mV at the current density of 2 mA/cm(2) and high mass activity of 1.08 A/mg(pt) (7.2 times higher than that of commercial Pt/C catalysts). Also, it shows an enhancement of 3.2 and 2.7 times in the mass and specific activities toward oxygen reduction reaction (ORR) compared to that of Pt/C. Moreover, it possesses an excellent catalytic durability for both ORR and HER. Even after 10,000 cycles, its ORR mass activity retains 87% of its initial value. The density functional theory (DFT) calculations demonstrate that by introducing Cu atoms into the Pt lattice, a downshift of the D-band center and favorable hydrogen adsorption free energy of approaching to zero (Delta G) occur, indicating the increased electrocatalytic activity of Pt electrocatalysts. (C) 2019 Elsevier Inc. All rights reserved. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000486104500017 | Publication Date | 2019-06-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-9517 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.844 | Times cited | 25 | Open Access | |
Notes | ; Z-Y. Hu thank for the support of “the Fundamental Research Funds for the Central Universities (WUT: 2017111055, 2018111039GX, 2018IVA095)”. S. Mu and J. Zhang acknowledges the support from the National Natural Science Foundation of China (NSFC) through award Nos. 51672204 and 21875221 and the opening funds of State Key Laboratory of Advanced Technology for Materials Synthesis and Processing (2019-KF-13), Wuhan University of Technology. ; | Approved | Most recent IF: 6.844 | ||
Call Number | UA @ admin @ c:irua:162903 | Serial | 5391 | ||
Permanent link to this record | |||||
Author | Li, T.; Piltz, B.; Podola, B.; Dron, A.; de Beer, D.; Melkonian, M. | ||||
Title | Microscale profiling of photosynthesis-related variables in a highly productive biofilm photobioreactor | Type | A1 Journal article | ||
Year | 2016 | Publication | Biotechnology and bioengineering | Abbreviated Journal | |
Volume | 113 | Issue | 5 | Pages | 1046-1055 |
Keywords | A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | In the present study depth profiles of light, oxygen, pH and photosynthetic performance in an artificial biofilm of the green alga Halochlorella rubescens in a porous substrate photobioreactor (PSBR) were recorded with microsensors. Biofilms were exposed to different light intensities (50-1,000mol photons m(-2) s(-1)) and CO2 levels (0.04-5% v/v in air). The distribution of photosynthetically active radiation showed almost identical trends for different surface irradiances, namely: a relatively fast drop to a depth of about 250 mu m, (to 5% of the incident), followed by a slower decrease. Light penetrated into the biofilm deeper than the Lambert-Beer Law predicted, which may be attributed to forward scattering of light, thus improving the overall light availability. Oxygen concentration profiles showed maxima at a depth between 50 and 150m, depending on the incident light intensity. A very fast gas exchange was observed at the biofilm surface. The highest oxygen concentration of 3.2mM was measured with 1,000mol photons m(-2) s(-1) and 5% supplementary CO2. Photosynthetic productivity increased with light intensity and/or CO2 concentration and was always highest at the biofilm surface; the stimulating effect of elevated CO2 concentration in the gas phase on photosynthesis was enhanced by higher light intensities. The dissolved inorganic carbon concentration profiles suggest that the availability of the dissolved free CO2 has the strongest impact on photosynthetic productivity. The results suggest that dark respiration could explain previously observed decrease in growth rate over cultivation time in this type of PSBR. Our results represent a basis for understanding the complex dynamics of environmental variables and metabolic processes in artificial phototrophic biofilms exposed to a gas phase and can be used to improve the design and operational parameters of PSBRs. Biotechnol. Bioeng. 2016;113: 1046-1055. (c) 2015 Wiley Periodicals, Inc. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000373476700013 | Publication Date | 2015-10-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0006-3592 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:133255 | Serial | 8248 | ||
Permanent link to this record | |||||
Author | Li, S.; Sun, J.; Gorbanev, Y.; van’t Veer, K.; Loenders, B.; Yi, Y.; Kenis, T.; Chen, Q.; Bogaerts, A. | ||||
Title | Plasma-Assisted Dry Reforming of CH4: How Small Amounts of O2Addition Can Drastically Enhance the Oxygenate Production─Experiments and Insights from Plasma Chemical Kinetics Modeling | Type | A1 Journal Article | ||
Year | 2023 | Publication | ACS Sustainable Chemistry & Engineering | Abbreviated Journal | ACS Sustainable Chem. Eng. |
Volume | 11 | Issue | 42 | Pages | 15373-15384 |
Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | Plasma-based dry reforming of methane (DRM) into high-value-added oxygenates is an appealing approach to enable otherwise thermodynamically unfavorable chemical reactions at ambient pressure and near room temperature. However, it suffers from coke deposition due to the deep decomposition of CH4. In this work, we assess the DRM performance upon O2 addition, as well as varying temperature, CO2/CH4 ratio, discharge power, and gas residence time, for optimizing oxygenate production. By adding O2, the main products can be shifted from syngas (CO + H2) toward oxygenates. Chemical kinetics modeling shows that the improved oxygenate production is due to the increased concentration of oxygen-containing radicals, e.g., O, OH, and HO2, formed by electron impact dissociation [e + O2 → e + O + O/O(1D)] and subsequent reactions with H atoms. Our study reveals the crucial role of oxygen-coupling in DRM aimed at oxygenates, providing practical solutions to suppress carbon deposition and at the same time enhance the oxygenates production in plasma-assisted DRM. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 001082603900001 | Publication Date | 2023-10-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2168-0485 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.4 | Times cited | Open Access | Not_Open_Access | |
Notes | Fonds Wetenschappelijk Onderzoek, S001619N ; China Scholarship Council, 202006060029 ; National Natural Science Foundation of China, 21975018 ; H2020 European Research Council, 810182 ; | Approved | Most recent IF: 8.4; 2023 IF: 5.951 | ||
Call Number | PLASMANT @ plasmant @c:irua:201013 | Serial | 8966 | ||
Permanent link to this record | |||||
Author | Li, S.; Ahmed, R.; Yi, Y.; Bogaerts, A. | ||||
Title | Methane to Methanol through Heterogeneous Catalysis and Plasma Catalysis | Type | A1 Journal article | ||
Year | 2021 | Publication | Catalysts | Abbreviated Journal | Catalysts |
Volume | 11 | Issue | 5 | Pages | 590 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Direct oxidation of methane to methanol (DOMTM) is attractive for the increasing industrial demand of feedstock. In this review, the latest advances in heterogeneous catalysis and plasma catalysis for DOMTM are summarized, with the aim to pinpoint the differences between both, and to provide some insights into their reaction mechanisms, as well as the implications for future development of highly selective catalysts for DOMTM. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000653609900001 | Publication Date | 2021-05-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2073-4344 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.082 | Times cited | Open Access | OpenAccess | |
Notes | Fundamental Research Funds for the Central Universities of China, DUT18JC42 ; National Natural Science Foundation of China, 21503032 ; PetroChina Innovation Foundation, 2018D-5007-0501 ; TOP-BOF research project of the Research Council of the University of Antwerp, 32249 ; This research was funded by the Fundamental Research Funds for the Central Universities of China (DUT18JC42), the National Natural Science Foundation of China (21503032) PetroChina Innovation Foundation (2018D-5007-0501) and the TOP-BOF research project of the Research Council of the University of Antwerp (grant ID 32249). This research was supported by the China Scholarship Council (CSC). The authors warmly acknowledge CSC for their support. | Approved | Most recent IF: 3.082 | ||
Call Number | PLASMANT @ plasmant @c:irua:177851 | Serial | 6753 | ||
Permanent link to this record | |||||
Author | Li, Q.N.; Xu, W.; Xiao, Y.M.; Ding, L.; Van Duppen, B.; Peeters, F.M. | ||||
Title | Optical absorption window in Na₃Bi based three-dimensional Dirac electronic system | Type | A1 Journal article | ||
Year | 2020 | Publication | Journal Of Applied Physics | Abbreviated Journal | J Appl Phys |
Volume | 128 | Issue | 15 | Pages | 155707 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a detailed theoretical study of the optoelectronic properties of a Na3Bi based three-dimensional Dirac electronic system (3DDES). The optical conductivity is evaluated using the energy-balance equation derived from a Boltzmann equation, where the electron Hamiltonian is taken from a simplified k . p approach. We find that for short-wavelength irradiation, the optical absorption in Na3Bi is mainly due to inter-band electronic transitions. In contrast to the universal optical conductance observed for graphene, the optical conductivity for Na3Bi based 3DDES depends on the radiation frequency but not on temperature, carrier density, and electronic relaxation time. In the radiation wavelength regime of about 5 mu m, < lambda < 200 mu m, an optical absorption window is found. This is similar to what is observed in graphene. The position and width of the absorption window depend on the direction of the light polarization and sensitively on temperature, carrier density, and electronic relaxation time. Particularly, we demonstrate that the inter-band optical absorption channel can be switched on and off by applying the gate voltage. This implies that similar to graphene, Na3Bi based 3DDES can also be applied in infrared electro-optical modulators. Our theoretical findings are helpful in gaining an in-depth understanding of the basic optoelectronic properties of recently discovered 3DDESs. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000585807400004 | Publication Date | 2020-10-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 3.2 | Times cited | 1 | Open Access | |
Notes | ; This work was supported by the National Natural Science Foundation of China (NNSFC Nos. U1930116, U1832153, 11764045, 11574319, and 11847054) and the Center of Science and Technology of Hefei Academy of Science (No. 2016FXZY002). Applied Basic Research Foundation of Department of Science and Technology of Yunnan Province (No. 2019FD134), the Department of Education of Yunnan Province (No. 2018JS010), the Young Backbone Teachers Training Program of Yunnan University, and the Department of Science and Technology of Yunnan Province are acknowledged. ; | Approved | Most recent IF: 3.2; 2020 IF: 2.068 | ||
Call Number | UA @ admin @ c:irua:173591 | Serial | 6571 | ||
Permanent link to this record | |||||
Author | Li, Q.; Niklas, K.J.J.; Niinemets, U.; Zhang, L.; Yu, K.; Gielis, J.; Gao, J.; Shi, P. | ||||
Title | Stomatal shape described by a superellipse in four Magnoliaceae species | Type | A1 Journal article | ||
Year | 2023 | Publication | Botany letters | Abbreviated Journal | |
Volume | Issue | Pages | 1-9 | ||
Keywords | A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | Stomata are essential for the exchange of water vapour and atmospheric gases between vascular plants and their external environments. The stomatal geometries of many plants appear to be elliptical. However, prior studies have not tested whether this is a mathematical reality, particularly since many natural shapes that appear to be ellipses are superellipses with greater or smaller edge curvature than predicted for an ellipse. Compared with the ellipse equation, the superellipse equation includes an additional parameter that allows generation of a larger range of shapes. We randomly selected 240 stomata from each of four Magnoliaceae species to test whether the stomatal geometries are superellipses or ellipses. The stomatal geometries for most stomata (943/960) were found to be described better using the superellipse equation. The traditional “elliptical stomata hypothesis” resulted in an underestimation of the area of stomata, whereas the superellipse equation accurately predicted stomatal area. This finding has important implications for the estimation of stomatal area in studies looking at stomatal shape, geometry, and function. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 001024190300001 | Publication Date | 2023-07-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2381-8107; 2381-8115 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 1.5 | Times cited | Open Access | Not_Open_Access: Available from 12.01.2024 | |
Notes | Approved | Most recent IF: 1.5; 2023 IF: NA | |||
Call Number | UA @ admin @ c:irua:197847 | Serial | 8935 | ||
Permanent link to this record | |||||
Author | Li, M.-R.; Deng, Z.; Lapidus, S.H.; Stephens, P.W.; Segre, C.U.; Croft, M.; Sena, R.P.; Hadermann, J.; Walker, D.; Greenblatt, M. | ||||
Title | Ba-3(Cr0.97(1)Te0.03(1))(2)TeO9: in Search of Jahn-Teller Distorted Cr(II) Oxide | Type | A1 Journal article | ||
Year | 2016 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
Volume | 55 | Issue | 55 | Pages | 10135-10142 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A novel 6H-type hexagonal perovskite Ba-3(Cr0.97(1)Te0.03(1))(2)TeO9 was prepared at high pressure (6 GPa) and temperature (1773 K). Both transmission electron microscopy and synchrotron powder X-ray diffraction data demonstrate that Ba-3(Cr0.97(1)Te0.03(1))(2)TeO9 crystallizes in P6(3)/mmc with face-shared (Cr0.97(1)Te0.03(1))O-6 octahedral pairs interconnected with TeO6 octahedra via corner-sharing. Structure analysis shows a mixed Cr2+/Cr3+ valence state with similar to 10% Cr2+. The existence of Cr2+ in Ba-3(Cr0.10(1)2+Cr0.87(1)3+Te0.036+)(2)TeO9 is further evidenced by X-ray absorption near-edge spectroscopy. Magnetic properties measurements show a paramagnetic response down to 4 K and a small glassy-state curvature at low temperature. In this work, the octahedral Cr2+O6 component is stabilized in an oxide material for the first time; the expected Jahn-Teller distortion of high-spin (d(4)) Cr2+ is not found, which is attributed to the small proportion of Cr2+ (similar to 10%) and the face-sharing arrangement of CrO6 octahedral pairs, which structurally disfavor axial distortion. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Easton, Pa | Editor | ||
Language | Wos | 000385785700026 | Publication Date | 2016-09-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0020-1669 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.857 | Times cited | 2 | Open Access | |
Notes | Approved | Most recent IF: 4.857 | |||
Call Number | UA @ lucian @ c:irua:140313 | Serial | 4440 | ||
Permanent link to this record | |||||
Author | Li, L.L.; Zarenia, M.; Xu, W.; Dong, H.M.; Peeters, F.M. | ||||
Title | Exciton states in a circular graphene quantum dot: Magnetic field induced intravalley to intervalley transition | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 95 | Issue | 95 | Pages | 045409 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The magnetic-field dependence of the energy spectrum, wave function, binding energy, and oscillator strength of exciton states confined in a circular graphene quantum dot (CGQD) is obtained within the configuration interaction method. We predict that (i) excitonic effects are very significant in the CGQD as a consequence of a combination of geometric confinement, magnetic confinement, and reduced screening; (ii) two types of excitons (intravalley and intervalley) are present in the CGQD because of the valley degree of freedom in graphene; (iii) the intravalley and intervalley exciton states display different magnetic-field dependencies due to the different electron-hole symmetries of the single-particle energy spectra; (iv) with increasing magnetic field, the exciton ground state in the CGQD undergoes an intravalley to intervalley transition accompanied by a change of angular momentum; (v) the exciton binding energy does not increase monotonically with the magnetic field due to the competition between geometric and magnetic confinements; and (vi) the optical transitions of the intervalley and intravalley excitons can be tuned by the magnetic field, and valley-dependent excitonic transitions can be realized in a CGQD. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000391856000006 | Publication Date | 2017-01-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 14 | Open Access | |
Notes | ; This work was financially supported by the China Scholarship Council (CSC), the Flemish Science Foundation (FWO-Vl), the National Natural Science Foundation of China (Grants No. 11304316, No. 11574319, and No. 11604380), and by the Chinese Academy of Sciences (CAS). ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:141444 | Serial | 4555 | ||
Permanent link to this record | |||||
Author | Li, L.L.; Xu, W.; Peeters, F.M. | ||||
Title | Intrinsic optical anisotropy of [001]-grown short-period InAs/GaSb superlattices | Type | A1 Journal article | ||
Year | 2010 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 82 | Issue | 23 | Pages | 235422-235422,10 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We theoretically investigate the intrinsic optical anisotropy or polarization induced by the microscopic interface asymmetry (MIA) in no-common-atom (NCA) InAs/GaSb superlattices (SLs) grown along the [001] direction. The eight-band K⋅P model is used to calculate the electronic band structures and incorporates the MIA effect. A Boltzmann equation approach is employed to calculate the optical properties. We found that in NCA InAs/GaSb SLs, the MIA effect causes a large in-plane optical anisotropy for linearly polarized light and the largest anisotropy occurs for light polarized along the [110] and [11̅ 0] directions. The relative difference between the optical-absorption coefficient for [110]-polarized light and that for [11̅ 0]-polarized light is found to be larger than 50%. The dependence of the in-plane optical anisotropy on temperature, photoexcited carrier density, and layer width is examined in detail. This study is important for optical devices which require the polarization control and selectivity. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000286768800007 | Publication Date | 2010-12-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 18 | Open Access | |
Notes | ; This work was supported partly by the Flemish Science Foundation (FWO-VL), the Belgium Science Policy (IAP), the NSF of China (Grants No. 10664006, No. 10504036, and No. 90503005), Special Funds of 973 Project of China (Grant No. 2005CB623603), and Knowledge Innovation Program of the Chinese Academy of Sciences. ; | Approved | Most recent IF: 3.836; 2010 IF: 3.774 | ||
Call Number | UA @ lucian @ c:irua:88909 | Serial | 1717 | ||
Permanent link to this record | |||||
Author | Li, L.L.; Xu, W.; Peeters, F.M. | ||||
Title | Optical conductivity of topological insulator thin films | Type | A1 Journal article | ||
Year | 2015 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 117 | Issue | 117 | Pages | 175305 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a detailed theoretical study on the optoelectronic properties of topological insulator thin film (TITFs). The k . p approach is employed to calculate the energy spectra and wave functions for both the bulk and surface states in the TITF. With these obtained results, the optical conductivities induced by different electronic transitions among the bulk and surface states are evaluated using the energy-balance equation derived from the Boltzmann equation. We find that for Bi2Se3-based TITFs, three characteristic regimes for the optical absorption can be observed. (i) In the low radiation frequency regime (photon energy (h) over bar omega < 200 meV), the free-carrier absorption takes place due to intraband electronic transitions. An optical absorption window can be observed. (ii) In the intermediate radiation frequency regime (200 < (h) over bar omega < 300 meV), the optical absorption is induced mainly by interband electronic transitions from surface states in the valance band to surface states in the conduction band and an universal value sigma(0) = e(2) / (8<(h)over bar>) for the optical conductivity can be obtained. (iii) In the high radiation frequency regime ((h) over bar omega > 300 meV), the optical absorption can be achieved via interband electronic transitions from bulk and surface states in the valance band to bulk and surface states in the conduction band. A strong absorption peak can be observed. These interesting findings indicate that optical measurements can be applied to identify the energy regimes of bulk and surface states in the TITF. (C) 2015 AIP Publishing LLC. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000354984100615 | Publication Date | 2015-05-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
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 | 9 | Open Access | |
Notes | ; This work was supported by the National Natural Science Foundation of China (Grant No. 11304316), Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; | Approved | Most recent IF: 2.068; 2015 IF: 2.183 | ||
Call Number | c:irua:126412 | Serial | 2473 | ||
Permanent link to this record | |||||
Author | Li, L.L.; Peeters, F.M. | ||||
Title | Quantum transport in defective phosphorene nanoribbons : effects of atomic vacancies | Type | A1 Journal article | ||
Year | 2018 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 97 | Issue | 7 | Pages | 075414 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Defects are almost inevitably present in realistic materials and defective materials are expected to exhibit very different properties than their nondefective (perfect) counterparts. Here, using a combination of the tight-binding approach and the scattering matrix formalism, we investigate the electronic transport properties of defective phosphorene nanoribbons (PNRs) containing atomic vacancies. We find that for both armchair PNRs (APNRs) and zigzag PNRs (ZPNRs), single vacancies can create quasilocalized states, which can affect their conductance. With increasing vacancy concentration, three different transport regimes are identified: ballistic, diffusive, and Anderson localized ones. In particular, ZPNRs that are known to be metallic due to the presence of edge states become semiconducting: edge conductance vanishes and transport gap appears due to Anderson localization. Moreover, we find that for a fixed vacancy concentration, both APNRs and ZPNRs of narrower width and/or longer length are more sensitive to vacancy disorder than their wider and/or shorter counterparts, and that for the same ribbon length and width, ZPNRs are more sensitive to vacancy disorder than APNRs. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000424901800006 | Publication Date | 2018-02-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
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 | 30 | Open Access | |
Notes | ; This work was financially supported by the Flemish Science Foundation (FWO-Vl), the FLAG-ERA TRANS 2D TMD, and by the Chinese Academy of Sciences (CAS). ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:149255UA @ admin @ c:irua:149255 | Serial | 4946 | ||
Permanent link to this record | |||||
Author | Li, L.L.; Peeters, F.M. | ||||
Title | Strain engineered linear dichroism and Faraday rotation in few-layer phosphorene | Type | A1 Journal article | ||
Year | 2019 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 114 | Issue | 24 | Pages | 243102 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We investigate theoretically the linear dichroism and the Faraday rotation of strained few-layer phosphorene, where strain is applied uniaxially along the armchair or zigzag direction of the phosphorene lattice. We calculate the optical conductivity tensor of uniaxially strained few-layer phosphorene by means of the Kubo formula within the tight-binding approach. We show that the linear dichroism and the Faraday rotation of few-layer phosphorene can be significantly modulated by the applied strain. The modulation depends strongly on both the magnitude and direction of strain and becomes more pronounced with increasing number of phosphorene layers. Our results are relevant for mechano-optoelectronic applications based on optical absorption and Hall effects in strained few-layer phosphorene. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000472599100029 | Publication Date | 2019-06-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 12 | Open Access | |
Notes | ; This work was financially supported by the Flemish Science Foundation (FWO-Vl) and by the FLAG-ERA Project TRANS-2D-TMD. ; | Approved | Most recent IF: 3.411 | ||
Call Number | UA @ admin @ c:irua:161327 | Serial | 5428 | ||
Permanent link to this record | |||||
Author | Li, L.L.; Partoens, B.; Xu, W.; Peeters, F.M. | ||||
Title | Electric-field modulation of linear dichroism and Faraday rotation in few-layer phosphorene | Type | A1 Journal article | ||
Year | 2019 | Publication | 2D materials | Abbreviated Journal | 2D Mater |
Volume | 6 | Issue | 1 | Pages | 015032 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Electro-optical modulators, which use an electric voltage (or an electric field) to modulate a beam of light, are essential elements in present-day telecommunication devices. Using a self-consistent tight-binding approach combined with the standard Kubo formula, we show that the optical conductivity and the linear dichroism of few-layer phosphorene can be modulated by a perpendicular electric field. We find that the field-induced charge screening plays a significant role in modulating the optical conductivity and the linear dichroism. Distinct absorption peaks are induced in the conductivity spectrum due to the strong quantum confinement along the out-of-plane direction and to the field-induced forbidden-to-allowed transitions. The field modulation of the linear dichroism becomes more pronounced with increasing number of phosphorene layers. We also show that the Faraday rotation is present in few-layer phosphorene even in the absence of an external magnetic field. This optical Hall effect is induced by the reduced lattice symmetry of few-layer phosphorene. The Faraday rotation is greatly influenced by the field-induced charge screening and is strongly dependent on the strength of perpendicular electric field and on the number of phosphorene layers. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000454321100002 | Publication Date | 2018-11-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2053-1583 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.937 | Times cited | 23 | Open Access | |
Notes | ; This work was financially supported by the Flemish Science Foundation (FWO-Vl) and by the FLAG-ERA project TRANS-2D-TMD. ; | Approved | Most recent IF: 6.937 | ||
Call Number | UA @ admin @ c:irua:156776 | Serial | 5207 | ||
Permanent link to this record | |||||
Author | Li, L.L.; Partoens, B.; Peeters, F.M. | ||||
Title | Tuning the electronic properties of gated multilayer phosphorene : a self-consistent tight-binding study | Type | A1 Journal article | ||
Year | 2018 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 97 | Issue | 15 | Pages | 155424 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | By taking account of the electric-field-induced charge screening, a self-consistent calculation within the framework of the tight-binding approach is employed to obtain the electronic band structure of gated multilayer phosphorene and the charge densities on the different phosphorene layers. We find charge density and screening anomalies in single-gated multilayer phosphorene and electron-hole bilayers in dual-gated multilayer phosphorene. Due to the unique puckered lattice structure, both intralayer and interlayer charge screenings are important in gated multilayer phosphorene. We find that the electric-field tuning of the band structure of multilayer phosphorene is distinctively different in the presence and absence of charge screening. For instance, it is shown that the unscreened band gap of multilayer phosphorene decreases dramatically with increasing electric-field strength. However, in the presence of charge screening, the magnitude of this band-gap decrease is significantly reduced and the reduction depends strongly on the number of phosphorene layers. Our theoretical results of the band-gap tuning are compared with recent experiments and good agreement is found. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000430459400005 | Publication Date | 2018-04-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
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 | 26 | Open Access | |
Notes | ; This work was financially supported by the Flemish Science Foundation (FWO-Vl). ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:150752UA @ admin @ c:irua:150752 | Serial | 4988 | ||
Permanent link to this record | |||||
Author | Li, L.L.; Moldovan, D.; Xu, W.; Peeters, F.M. | ||||
Title | Electric-and magnetic-field dependence of the electronic and optical properties of phosphorene quantum dots | Type | A1 Journal article | ||
Year | 2017 | Publication | Nanotechnology | Abbreviated Journal | Nanotechnology |
Volume | 28 | Issue | 8 | Pages | 085702 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Recently, black phosphorus quantum dots were fabricated experimentally. Motivated by these experiments, we theoretically investigate the electronic and optical properties of rectangular phosphorene quantum dots (RPQDs) in the presence of an in-plane electric field and a perpendicular magnetic field. The energy spectra and wave functions of RPQDs are obtained numerically using the tight-binding approach. We find edge states within the band gap of the RPQD which are well separated from the bulk states. In an undoped RPQD and for in-plane polarized light, due to the presence of well-defined edge states, we find three types of optical transitions which are between the bulk states, between the edge and bulk states, and between the edge states. The electric and magnetic fields influence the bulk-to-bulk, edge-to-bulk, and edge-to- edge transitions differently due to the different responses of bulk and edge states to these fields. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Bristol | Editor | ||
Language | Wos | 000403100700001 | Publication Date | 2017-01-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0957-4484 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.44 | Times cited | 32 | Open Access | |
Notes | ; This work was financially supported by the China Scholarship Council (CSC), the Flemish Science Foundation (FWO-Vl), the National Natural Science Foundation of China (Grant Nos. 11304316 and 11574319), and by the Chinese Academy of Sciences (CAS). ; | Approved | Most recent IF: 3.44 | ||
Call Number | UA @ lucian @ c:irua:144325 | Serial | 4648 | ||
Permanent link to this record | |||||
Author | Li, L.L.; Moldovan, D.; Xu, W.; Peeters, F.M. | ||||
Title | Electronic properties of bilayer phosphorene quantum dots in the presence of perpendicular electric and magnetic fields | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 96 | Issue | 15 | Pages | 155425 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using the tight-binding approach, we investigate the electronic properties of bilayer phosphorene (BLP) quantum dots (QDs) in the presence of perpendicular electric and magnetic fields. Since BLP consists of two coupled phosphorene layers, it is of interest to examine the layer-dependent electronic properties of BLP QDs, such as the electronic distributions over the two layers and the so-produced layer-polarization features, and to see how these properties are affected by the magnetic field and the bias potential. We find that in the absence of a bias potential only edge states are layer polarized while the bulk states are not, and the layer-polarization degree (LPD) of the unbiased edge states increases with increasing magnetic field. However, in the presence of a bias potential both the edge and bulk states are layer polarized, and the LPD of the bulk (edge) states depends strongly (weakly) on the interplay of the bias potential and the interlayer coupling. At high magnetic fields, applying a bias potential renders the bulk electrons in a BLP QD to be mainly distributed over the top or bottom layer, resulting in layer-polarized bulk Landau levels (LLs). In the presence of a large bias potential that can drive a semiconductor-to-semimetal transition in BLP, these bulk LLs exhibit different magnetic-field dependences, i.e., the zeroth LLs exhibit a linearlike dependence on the magnetic field while the other LLs exhibit a square-root-like dependence. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000412699800005 | Publication Date | 2017-10-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
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 | 28 | Open Access | |
Notes | ; This work was financially supported by the Flemish Science Foundation (FWO-Vl), the National Natural Science Foundation of China (Grant No. 11574319), and the Chinese Academy of Sciences. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:146686 | Serial | 4782 | ||
Permanent link to this record | |||||
Author | Li, L.L.; Moldovan, D.; Vasilopoulos, P.; Peeters, F.M. | ||||
Title | Aharonov-Bohm oscillations in phosphorene quantum rings | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 95 | Issue | 20 | Pages | 205426 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The Aharonov-Bohm (AB) effect in square phosphorene quantum rings, with armchair and zigzag edges, is investigated using the tight-binding method. The energy spectra and wave functions of such rings, obtained as a function of the magnetic flux Phi threading the ring, are strongly influenced by the ringwidthW, an in-plane electric field E-p, and a side-gating potential V-g. Compared to a square dot, the ring shows an enhanced confinement due to its inner edges and an interedge coupling along the zigzag direction, both of which strongly affect the energy spectrum and the wave functions. The energy spectrum that is gapped consists of a regular part, of conduction (valence) band states, that shows the usual AB oscillations in the higher-(lower-) energy region, and of edge states, in the gap, that exhibit no AB oscillations. As the width W decreases, the AB oscillations become more distinct and regular and their period is close to Phi(0)/2, where the flux quantum Phi(0) = h/e is the period of an ideal circular ring (W -> 0). Both the electric field E-p and the side-gating potential V-g reduce the amplitude of the AB oscillations. The amplitude can be effectively tuned by E-p or V-g and exhibits an anisotropic behavior for different field directions or side-gating configurations. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000402003700010 | Publication Date | 2017-05-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
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 | 16 | Open Access | |
Notes | ; This work was financially supported by the Chinese Academy of Sciences, the Flemish Science Foundation (FWO-V1), and by the Canadian NSERC Grant No. OGP0121756 (P.V.). ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:144267 | Serial | 4638 | ||
Permanent link to this record | |||||
Author | Li, L.L.; Gillen, R.; Palummo, M.; Milošević, M.V.; Peeters, F.M. | ||||
Title | Strain tunable interlayer and intralayer excitons in vertically stacked MoSe₂/WSe₂ heterobilayers | Type | A1 Journal article | ||
Year | 2023 | Publication | Applied physics letters | Abbreviated Journal | |
Volume | 123 | Issue | 3 | Pages | 033102-33106 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Recently, interlayer and intralayer excitons in transition metal dichalcogenide heterobilayers have been studied both experimentally and theoretically. In spite of a growing interest, these layer-resolved excitons in the presence of external stimuli, such as strain, remain not fully understood. Here, using density-functional theory calculations with many-body effects, we explore the excitonic properties of vertically stacked MoSe2/WSe2 heterobilayer in the presence of in-plane biaxial strain of up to 5%. We calculate the strain dependence of exciton absorption spectrum, oscillator strength, wave function, and binding energy by solving the Bethe-Salpeter equation on top of the standard GW approach. We identify the interlayer and intralayer excitons by analyzing their electron-hole weights and spatial wave functions. We show that with the increase in strain magnitude, the absorption spectrum of the interlayer and intralayer excitons is red-shifted and re-ordered, and the binding energies of these layer-resolved excitons decrease monotonically and almost linearly. We derive the sensitivity of exciton binding energy to the applied strain and find that the intralayer excitons are more sensitive to strain than the interlayer excitons. For instance, a sensitivity of -7.9 meV/% is derived for the intra-MoSe2-layer excitons, which is followed by -7.4 meV/% for the intra-WSe2-layer excitons, and by -4.2 meV/% for the interlayer excitons. Our results indicate that interlayer and intralayer excitons in vertically stacked MoSe2/WSe2 heterobilayer are efficiently tunable by in-plane biaxial strain. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 001033604700003 | Publication Date | 2023-07-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4 | Times cited | 2 | Open Access | OpenAccess |
Notes | Approved | Most recent IF: 4; 2023 IF: 3.411 | |||
Call Number | UA @ admin @ c:irua:198382 | Serial | 8823 | ||
Permanent link to this record |