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| Author | Batuk, M.; Vandemeulebroucke, D.; Ceretti, M.; Paulus, W.; Hadermann, J. | ||||
| Title | Topotactic redox cycling in SrFeO2.5+δ explored by 3D electron diffraction in different gas atmospheres | Type | A1 Journal article | ||
| Year | 2022 | Publication | Journal of materials chemistry A : materials for energy and sustainability | Abbreviated Journal | J Mater Chem A |
| Volume | Issue | Pages | |||
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | For oxygen conducting materials applied in solid oxide fuel cells and chemical-looping processes, the understanding of the oxygen diffusion mechanism and the materials’ crystal structure at different stages of the redox reactions is a key parameter to control their performance. In this paper we report the first ever in situ 3D ED experiment in a gas environment and with it uncover the structure evolution of SrFeO2.5 as notably different from that reported from in situ X-ray and in situ neutron powder diffraction studies in gas environments. Using in situ 3D ED on submicron sized single crystals obtained from a high quality monodomain SrFeO2.5 single crystal , we observe the transformation under O2 flow of SrFeO2.5 with an intra- and interlayer ordering of the left and right twisted (FeO4) tetrahedral chains (space group Pcmb) into consecutively SrFeO2.75 with space group Cmmm (at 350°C, 33% O2) and SrFeO3-δ with space group Pm3 ̅m (at 400°C, 100% O2). Upon reduction in H2 flow, the crystals return to the brownmillerite structure with intralayer order, but without regaining the interlayer order of the pristine crystals. Therefore, redox cycling of SrFeO2.5 crystals in O2 and H2 introduces stacking faults into the structure, resulting in an I2/m(0βγ)0s symmetry with variable β. | ||||
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| Language | Wos | 000891928400001 | Publication Date | 0000-00-00 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2050-7488 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 11.9 | Times cited | Open Access | OpenAccess | |
Notes  |
Financial support is acknowledged from the FWO-Hercules fund I003218N ‘Infrastructure for imaging nanoscale processes in gas/vapor or liquid environments’, from the University of Antwerp through grant BOF TOP 38689. This work was supported by the European Commission Horizon 2020 NanED grant number 956099. Financial support from the French National Research Agency (ANR) through the project “Structural induced Electronic Complexity controlled by low temperature Topotactic Reaction” (SECTOR No. ANR-14-CE36- 0006-01) is gratefully acknowledged. | Approved | Most recent IF: 11.9 | ||
| Call Number | EMAT @ emat @c:irua:192325 | Serial | 7229 | ||
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| Author | Deng, S.; Kurttepeli, M.; Cott, D.J.; Bals, S.; Detavernier, C. | ||||
| Title | Porous nanostructured metal oxides synthesized through atomic layer deposition on a carbonaceous template followed by calcination | Type | A1 Journal article | ||
| Year | 2015 | Publication | Journal of materials chemistry A : materials for energy and sustainability | Abbreviated Journal | J Mater Chem A |
| Volume | 3 | Issue | 3 | Pages | 2642-2649 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Porous metal oxides with nano-sized features attracted intensive interest in recent decades due to their high surface area which is essential for many applications, e.g. Li ion batteries, photocatalysts, fuel cells and dye-sensitized solar cells. Various approaches have so far been investigated to synthesize porous nanostructured metal oxides, including self-assembly and template-assisted synthesis. For the latter approach, forests of carbon nanotubes are considered as particularly promising templates, with respect to their one-dimensional nature and the resulting high surface area. In this work, we systematically investigate the formation of porous metal oxides (Al2O3, TiO2, V2O5 and ZnO) with different morphologies using atomic layer deposition on multi-walled carbon nanotubes followed by post-deposition calcination. X-ray diffraction, scanning electron microscopy accompanied by X-ray energy dispersive spectroscopy and transmission electron microscopy were used for the investigation of morphological and structural transitions at the micro- and nano-scale during the calcination process. The crystallization temperature and the surface coverage of the metal oxides and the oxidation temperature of the carbon nanotubes were found to produce significant influence on the final morphology. | ||||
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| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos | 000348990500019 | Publication Date | 2014-12-06 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2050-7488;2050-7496; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 8.867 | Times cited | 23 | Open Access | OpenAccess |
| Notes |
Fwo; 239865 Cocoon; 335078 Colouratoms; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); | Approved | Most recent IF: 8.867; 2015 IF: 7.443 | ||
| Call Number | c:irua:125298 | Serial | 2673 | ||
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| Author | Wee, L.H.; Meledina, M.; Turner, S.; Custers, K.; Kerkhofs, S.; Van Tendeloo, G.; Martens, J.A. | ||||
| Title | Hematite iron oxide nanorod patterning inside COK-12 mesochannels as an efficient visible light photocatalyst | Type | A1 Journal article | ||
| Year | 2015 | Publication | Journal of materials chemistry A : materials for energy and sustainability | Abbreviated Journal | J Mater Chem A |
| Volume | 3 | Issue | 3 | Pages | 19884-19891 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The uniform dispersion of functional oxide nanoparticles on the walls of ordered mesoporous silica to tailor optical, electronic, and magnetic properties for biomedical and environmental applications is a scientific challenge. Here, we demonstrate homogeneous confined growth of 5 nanometer-sized hematite iron oxide (α-Fe2O3) inside mesochannels of ordered mesoporous COK-12 nanoplates. The three-dimensional inclusion of the α-Fe2O3 nanorods in COK-12 particles is studied using high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), energy-dispersive X-ray (EDX) spectroscopy and electron tomography. High resolution imaging and EDX spectroscopy provide information about the particle size, shape and crystal phase of the loaded α-Fe2O3 material, while electron tomography provides detailed information on the spreading of the nanorods throughout the COK-12 host. This nanocomposite material, having a semiconductor band gap energy of 2.40 eV according to diffuse reflectance spectroscopy, demonstrates an improved visible light photocatalytic degradation activity with rhodamine 6G and 1-adamantanol model compounds. | ||||
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| Language | Wos | 000362041300033 | Publication Date | 2015-08-26 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2050-7488;2050-7496; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 8.867 | Times cited | 9 | Open Access | |
| Notes |
L.H.W. and S.T. thank the FWO-Vlaanderen for a postdoctoral research fellowship (12M1415N) and under contract number G004613N . J.A.M gratefully acknowledge financial supports from Flemish Government (Long-term structural funding-Methusalem). Collaboration among universities was supported by the Belgian Government (IAP-PAI network). | Approved | Most recent IF: 8.867; 2015 IF: 7.443 | ||
| Call Number | c:irua:132567 | Serial | 3959 | ||
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| Author | Zalfani, M.; van der Schueren, B.; Hu, Z.-Y.; Rooke, J.C.; Bourguiga, R.; Wu, M.; Li, Y.; Van Tendeloo, G.; Su, B.-L. | ||||
| Title | Novel 3DOM BiVO4/TiO2nanocomposites for highly enhanced photocatalytic activity | Type | A1 Journal article | ||
| Year | 2015 | Publication | Journal of materials chemistry A : materials for energy and sustainability | Abbreviated Journal | J Mater Chem A |
| Volume | 3 | Issue | 3 | Pages | 21244-21256 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Novel 3DOM BiVO4/TiO2 nanocomposites with intimate contact were for the first time synthesized by a hydrothermal method in order to elucidate their visible-light-driven photocatalytic performances. BiVO4 nanoparticles and 3DOM TiO2 inverse opal were fabricated respectively. These materials were characterized by XRD, XPS, SEM, TEM, N2 adsorption–desorption and UV-vis diffuse (UV-vis) and photoluminescence spectroscopies. As references for comparison, a physical mixture of BiVO4 nanoparticles and 3DOM TiO2 inverse opal powder (0.08 : 1), and a BiVO4/P25 TiO2 (0.08 : 1) nanocomposite made also by the hydrothermal method were prepared. The photocatalytic performance of all the prepared materials was evaluated by the degradation of rhodamine B (RhB) as a model pollutant molecule under visible light irradiation. The highly ordered 3D macroporous inverse opal structure can provide more active surface areas and increased mass transfer because of its highly accessible 3D porosity. The results show that 3DOM BiVO4/TiO2 nanocomposites possess a highly prolonged lifetime and increased separation of visible light generated charges and extraordinarily high photocatalytic activity. Owing to the intimate contact between BiVO4 and large surface area 3DOM TiO2, the photogenerated high energy charges can be easily transferred from BiVO4 to the 3DOM TiO2 support. BiVO4 nanoparticles in the 3DOM TiO2 inverse opal structure act thus as a sensitizer to absorb visible light and to transfer efficiently high energy electrons to TiO2 to ensure long lifetime of the photogenerated charges and keep them well separated, owing to the direct band gap of BiVO4 of 2.4 eV, favourably positioned band edges, very low recombination rate of electron–hole pairs and stability when coupled with photocatalysts, explaining the extraordinarily high photocatalytic performance of 3DOM BiVO4/TiO2 nanocomposites. It is found that larger the amount of BiVO4 in the nanocomposite, longer the duration of photogenerated charge separation and higher the photocatalytic activity. This work can shed light on the development of novel visible light responsive nanomaterials for efficient solar energy utilisation by the intimate combination of an inorganic light sensitizing nanoparticle with an inverse opal structure with high diffusion efficiency and high accessible surface area. | ||||
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| Language | Wos | 000363163200049 | Publication Date | 2015-09-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2050-7488;2050-7496; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 8.867 | Times cited | 88 | Open Access | |
| Notes |
This work was realized with the financial support of the Belgian FNRS (Fonds National de la Recherche Scientifique). This research used resources of the Electron Microscopy Service located at the University of Namur. This Service is a member of the “Plateforme Technologique Morphologie – Imagerie”. The XPS analyses were made in the LISE, Department of Physics of the University of Namur thanks to Dr P. Louette. This work was also supported by Changjiang Scholars and the Innovative Research Team (IRT1169) of the Ministry of Education of the People's Republic of China. B. L. Su acknowledges the Chinese Central Government for an “Expert of the State” position in the Program of the “Thousand Talents” and a Clare Hall Life Membership at the Clare Hall and the financial support of the Department of Chemistry, University of Cambridge. G. Van Tendeloo and Z. Y. Hu acknowledge support from the EC Framework 7 program ESTEEM2 (Reference 312483).; esteem2_jra4 | Approved | Most recent IF: 8.867; 2015 IF: 7.443 | ||
| Call Number | c:irua:129476 c:irua:129476 | Serial | 3951 | ||
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| Author | Pulinthanathu Sree, S.; Dendooven, J.; Geerts, L.; Ramachandran, R.K.; Javon, E.; Ceyssens, F.; Breynaert, E.; Kirschhock, C.E.A.; Puers, R.; Altantzis, T.; Van Tendeloo, G.; Bals, S.; Detavernier, C.; Martens, J.A. | ||||
| Title | 3D porous nanostructured platinum prepared using atomic layer deposition | Type | A1 Journal article | ||
| Year | 2017 | Publication | Journal of materials chemistry A : materials for energy and sustainability | Abbreviated Journal | J Mater Chem A |
| Volume | 5 | Issue | 5 | Pages | 19007-19016 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A robust and easy to handle 3D porous platinum structure was created via replicating the 3D channel system of an ordered mesoporous silica material using atomic layer deposition (ALD) over micrometer distances. After ALD of Pt in the silica material, the host template was digested using hydrogen fluoride (HF). A fully connected ordered Pt nanostructure was obtained with morphology and sizes corresponding to that of the pores of the host matrix, as revealed with high-resolution scanning transmission electron microscopy and electron tomography. The Pt nanostructure consisted of hexagonal Pt rods originating from the straight mesopores (11 nm) of the host structure and linking features resulting from Pt replication of the interconnecting mesopore segments (2–4 nm) present in the silica host structure. Electron tomography of partial replicas, made by incomplete infilling of Zeotile-4 material with Pt, provided insight in the connectivity and formation mechanism of the Pt nanostructure by ALD. The Pt replica was evaluated for its potential use as electrocatalyst for the hydrogen evolution reaction, one of the half-reactions of water electrolysis, and as microelectrode for biomedical sensing. The Pt replica showed high activity for the hydrogen evolution reaction and electrochemical characterization revealed a large impedance improvement in comparison with reference Pt electrodes. |
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| Language | Wos | 000411232100010 | Publication Date | 2017-06-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2050-7488 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 8.867 | Times cited | 9 | Open Access | OpenAccess |
| Notes |
This work was supported by the Flemish government through long-term structural funding (Methusalem) to JAM and FWO for a research project (G0A5417N). JD, TA and FC acknowledge Flemish FWO for a post-doctoral fellowship. S. B. acknowledges funding from ERC Starting Grant COLOURATOMS (335078). (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; | Approved | Most recent IF: 8.867 | ||
| Call Number | EMAT @ emat @ c:irua:144624 c:irua:144624 c:irua:144624UA @ admin @ c:irua:144624 | Serial | 4634 | ||
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| Author | Finizola e Silva, M.; Van Passel, S. | ||||
| Title | Climate-Smart Agriculture in the Northeast of Brazil: An Integrated Assessment of the Aquaponics Technology | Type | A1 Journal Article | ||
| Year | 2020 | Publication | Sustainability | Abbreviated Journal | Sustainability-Basel |
| Volume | 12 | Issue | 9 | Pages | 3734 |
| Keywords | A1 Journal Article; aquaponics; Aquaponova; Brazil; semi-arid region; food insecurity; cost–benefit analysis; socio-economic approach; climate-smart agriculture; Engineering Management (ENM) ; | ||||
| Abstract | The purpose of this study is to determine if aquaponic systems can reduce food insecurity in the semi-arid regions of Brazil and generate income for the beneficiaries. Aquaponics is a potentially sustainable way to produce food based on gardening, hydroponics and aquaculture. A case study, based on a project called Aquaponova, was developed. The aquaponic systems currently used in the project are non-commercial and designed for households with limited resources. The data based on six existing systems within this project were used to compare the costs and the benefits. The cost–benefit analysis covers four scenarios and three financing options. The results show that aquaponic systems have a large potential and can reduce food insecurity in semi-arid regions while generating income for the beneficiaries. Even if the system only produces 40% of the total estimated production, the system will still be feasible. However, the low opportunity cost of labour is an essential factor for obtaining these positive results. Moreover, the social benefits, such as a community spirit and the health benefits of the system, should not be underestimated. | ||||
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| Language | Wos | 000537476200232 | Publication Date | 2020-05-05 | |
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| ISSN | 2071-1050 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.9 | Times cited | Open Access | ||
| Notes |
We would like to express our gratitude to Francisco Fechine Borges who introduced Maíra Finizola e Silva the basics of aquaponics and gave her the opportunity to base her research on the data from the Aquaponova project. We would also like to thank the participants of the 2nd LA SDEWES conference in Buenos Aires (9–12 February 2020) for the useful comments and suggestions. | Approved | Most recent IF: 3.9; 2020 IF: 1.789 | ||
| Call Number | ENM @ enm @c:irua:170074 | Serial | 6382 | ||
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