|   | 
Details
   web
Records
Author Nikolaev, A.V.; Michel, K.H.
Title Ab initio approach to superexchange interactions in alkali doped fullerides AC60 Type P1 Proceeding
Year 2004 Publication AIP conference proceedings T2 – 18th International Winterschool/Euroconference on Electronic Properties, of Novel Materials, MAR 06-JUN 13, 2004, Kirchberg, AUSTRIA Abbreviated Journal
Volume (up) Issue Pages 393-396
Keywords P1 Proceeding; Condensed Matter Theory (CMT)
Abstract The superexchange interactions between the fullerenes arise as a result of the electron transfer from the C-60 molecule to the alkali atom and back. We present a scheme, which is a configuration interaction approach based on the valence bond (Heitler-London) method. The effect of superexchange is described together with chemical bonding by constructing and solving a secular equation, rather than by using a perturbation treatment. We have considered 180degrees and 90degrees superexchange for the C-60 Cs-C-60 pathways. The calculations account for unusual electronic properties of polymer orthorhombic and quenched cubic phases of CsC60: two lines in nuclear magnetic resonance experiments, the development of a spin-singlet ground state and a decrease of magnetic susceptibility as T-->0.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos 000224699400085 Publication Date 2004-11-11
Series Editor Series Title Abbreviated Series Title
Series Volume 723 Series Issue Edition
ISSN 0-7354-0204-3 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:103752 Serial 27
Permanent link to this record
 

 
Author Mortet, V.; Zhang, L.; Echert, M.; Soltani, A.; d' Haen, J.; Douheret, O.; Moreau, M.; Osswald, S.; Neyts, E.; Troadec, D.; Wagner, P.; Bogaerts, A.; Van Tendeloo, G.; Haenen, K.
Title Characterization of nano-crystalline diamond films grown under continuous DC bias during plasma enhanced chemical vapor deposition Type A3 Journal article
Year 2009 Publication Materials Research Society symposium proceedings Abbreviated Journal
Volume (up) Issue 1203 Pages
Keywords A3 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Nanocrystalline diamond films have generated much interested due to their diamond-like properties and low surface roughness. Several techniques have been used to obtain a high re-nucleation rate, such as hydrogen poor or high methane concentration plasmas. In this work, the properties of nano-diamond films grown on silicon substrates using a continuous DC bias voltage during the complete duration of growth are studied. Subsequently, the layers were characterised by several morphological, structural and optical techniques. Besides a thorough investigation of the surface structure, using SEM and AFM, special attention was paid to the bulk structure of the films. The application of FTIR, XRD, multi wavelength Raman spectroscopy, TEM and EELS yielded a detailed insight in important properties such as the amount of crystallinity, the hydrogen content and grain size. Although these films are smooth, they are under a considerable compressive stress. FTIR spectroscopy points to a high hydrogen content in the films, while Raman and EELS indicate a high concentration of sp2 carbon. TEM and EELS show that these films consist of diamond nano-grains mixed with an amorphous sp2 bonded carbon, these results are consistent with the XRD and UV Raman spectroscopy data.
Address
Corporate Author Thesis
Publisher Place of Publication Wuhan Editor
Language Wos Publication Date 2010-03-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1946-4274; ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:81646 Serial 327
Permanent link to this record
 

 
Author Fedina, L.; Gutakovskii, A.; Aseev, A.; van Landuyt, J.; Vanhellemont, J.
Title Clustering of vacancies on {113} planes in Si layers close to Si-Si3N4 interfaces and further aggregation of self-interstitials inside vacancy clusters during electron irradiation Type A1 Journal article
Year 1999 Publication Institute of physics conference series T2 – Conference on Microscopy of Semiconducting Materials, MAR 22-25, 1999, UNIV OXFORD, OXFORD, ENGLAND Abbreviated Journal Inst Phys Conf Ser
Volume (up) Issue 164 Pages 495-498
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In situ HREM irradiation of (110) FZ-Si crystals covered with thin Si3N4 films was carried out in a JEOL-4000EX microscope, operated at 400 keV at room temperature. It is found that clustering of vacancies on (113) planes is realised in a Si layer close to the Si-Si3N4 interface at the initial stage of irradiation. Further aggregation of self-interstitials inside vacancy clusters is considered as an alternative way of point defect recombination in extended shape, to be accomplished with the formation of the extended defects of interstitial type upon interstitial supersaturation.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000166835300106 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0-7503-0650-5; 0951-3248 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:102918 Serial 376
Permanent link to this record
 

 
Author Peirs, J.; Verleysen, P.; Tirry, W.; Rabet, L.; Schryvers, D.; Degrieck, J.
Title Dynamic shear localization in Ti6Al4V Type P1 Proceeding
Year 2011 Publication Procedia Engineering T2 – 11th International Conference on the Mechanical Behavior of Materials, (ICM), 2011, Como, ITALY (ICM11) Abbreviated Journal
Volume (up) Issue Pages 1-6
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract The alloy Ti6Al4V is known to be prone to the formation of adiabatic shear bands when dynamically loaded in shear. This causes a catastrophic decrease of the load carrying capacity and is usually followed by fracture. Although, the main mechanism is recognized to be the competition between strain hardening and thermal softening, a detailed understanding of the role of microstructural plasticity mechanisms and macroscopic loading conditions does not exist yet. To study strain localization and shear fracture, different high strain rate shear tests have been carried out: compression of hat-shaped specimens, torsion of thin walled tubular specimens and in-plane shear tests. The value of the three techniques in studying shear localization is evaluated. Post-mortem analysis of the fracture surface and the materials' microstructure is performed with optical and electron microscopy. In all cases a ductile fracture is observed. SEM and TEM techniques are used to study the local microstructure and composition in the shear band and as such the driving mechanism for the ASB formation. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of ICM11
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000300451302060 Publication Date 2011-06-20
Series Editor Series Title Abbreviated Series Title
Series Volume 10 Series Issue Edition
ISSN 1877-7058; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 4 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:113069 Serial 767
Permanent link to this record
 

 
Author Hens, S.; Bender, H.; Donaton, R.A.; Maex, K.; Vanhaelemeersch, S.; van Landuyt, J.
Title EFTEM study of plasma etched low-k Si-O-C dielectrics Type A1 Journal article
Year 2001 Publication Institute of physics conference series T2 – Royal-Microscopical-Society Conference on Microscopy of Semiconducting, Materials, MAR 25-29, 2001, UNIV OXFORD, OXFORD, ENGLAND Abbreviated Journal
Volume (up) Issue 169 Pages 415-418
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Materials with low dielectric constant ("low-k'') in combination with Cu metallization are replacing the oxide based dielectrics with Al metallization in future generations of micro-electronic devices. In this work, a carbon doped oxide low-k dielectric material is studied after different kinds of etch/strip steps in single damascene Cu. filled line structures. Interline capacitance measurements indicate a dependence of the dielectric constant on the strip conditions. EFTEM is used to study the composition of the dielectric material and the modification of the low-k material at the sidewall of the etched structures for the various treatment conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0-7503-0818-4; 0951-3248 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:103432 Serial 877
Permanent link to this record
 

 
Author Avetisyan, A.A.; Partoens, B.; Peeters, F.M.
Title Electric field tuning of the band gap in four layers of graphene with different stacking order Type P1 Proceeding
Year 2012 Publication Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – Conference on Photonics and Micro and Nano-structured Materials, JUN 28-30, 2011, Yerevan, ARMENIA Abbreviated Journal
Volume (up) Issue Pages 84140-84148
Keywords P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We investigated the effect of different stacking order of the four graphene layer system on the induced band gap when positively charged top and negatively charged back gates are applied to the system. A tight-binding approach within a self-consistent Hartree approximation is used to calculate the induced charges on the different graphene layers. We show that the electric field does not open an energy gap if the multilayer graphene system contains a trilayer part with the ABA Bernal stacking.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000303856600012 Publication Date 2012-01-20
Series Editor Series Title Abbreviated Series Title
Series Volume 8414 Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), and the BelgianScience Policy (IAP). One of us (A.A.A.) was supported by a fellowship from the Belgian Federal Science Policy Office (BELSPO). ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:113046 Serial 886
Permanent link to this record
 

 
Author Colomer, J.-F.; Henrard, L.; Lambin, P.; Van Tendeloo, G.
Title Electron diffraction of nanotubes bundles : unique helicity and tube-tube atomically coherent packing Type P1 Proceeding
Year 2002 Publication AIP conference proceedings T2 – 16th International Winterschool on Electronic Properties of Novel, Materials, MAR 02-09, 2002, KIRCHBERG, AUSTRIA Abbreviated Journal
Volume (up) Issue Pages 314-317
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract The atomic structure of single-wall carbon nanotube bundles produced by three different techniques has been characterized by electron diffraction and microscopy. Small bundles produced by Catalytical Chemical Vapor Deposition (CCVD) exhibit only one or two tube chiralities within a single bundle while bundles produced by arc-discharge or laser-ablation exhibit more chiralities. A detailed analysis of the central line of diffraction is also presented. The CCVD nanotubes present more intense spots around 1.7 Angstrom(-1) < k < 2Angstrom(-1) (k is the momentum transfer) compared to what is observed for nanotubes produced by other methods. Amongst the possible explanation for such an anomaly, we put forward that in this range of momentum transfer, the relative tube orientations and translations are important for what concerns the interpretation of the diffraction peaks intensities.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos 000178866600070 Publication Date 2003-02-26
Series Editor Series Title Abbreviated Series Title
Series Volume 633 Series Issue Edition
ISSN 0-7354-0088-1; 0094-243x ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:104172 Serial 921
Permanent link to this record
 

 
Author Van Tendeloo, G.; Amelinckx, S.
Title Electron-microscopy and the structural studies of superconducting materials and fullerites Type P1 Proceeding
Year 1994 Publication NATO Advanced Study Institutes series: series E : applied sciences T2 – NATO Advanced Study Institute on Materials and crystallographic Aspects, of HT(c)-Superconductivity, May 17-30, 1993, Erice, Italy Abbreviated Journal
Volume (up) Issue Pages 521-538
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Kluwer Academic Place of Publication Dordrecht Editor
Language Wos A1994BA54N00025 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume 263 Series Issue Edition
ISSN 0-7923-2773-X ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:95934 Serial 949
Permanent link to this record
 

 
Author Schryvers, D.; Ma, Y.; Toth, L.; Tanner, L.E.
Title EM study of twinning in the Ni5Al3 bainitic phase Type A3 Journal article
Year 1993 Publication Twinning in advanced materials Abbreviated Journal
Volume (up) Issue Pages 395-402
Keywords A3 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1994BB13P00037 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved PHYSICS, APPLIED 28/145 Q1 #
Call Number UA @ lucian @ c:irua:48358 Serial 1031
Permanent link to this record
 

 
Author Nistor, L.; Bender, H.; van Landuyt, J.; Nemeth, S.; Boeve, H.; De Boeck, J.; Borghs, G.
Title HREM investigation of a Fe/GaN/Fe tunnel junction Type A1 Journal article
Year 2001 Publication Institute of physics conference series T2 – Royal-Microscopical-Society Conference on Microscopy of Semiconducting, Materials, MAR 25-29, 2001, Univ of Oxford, Oxford, England Abbreviated Journal
Volume (up) Issue 169 Pages 53-56
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The structure of Fe/GaN/Fe ferromagnetic electrodes is studied by high resolution transmission electron microscopy. The layers grow epitaxially on the GaAs substrate with the top Fe layer 90degrees rotated compared to the bottom one. The interfaces are quite rough. There is an indication of the possible occurrence of Fe3GaAs formation on the GaAs interface.
Address
Corporate Author Thesis
Publisher IOP Publishing Place of Publication Bristol Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0-7503-0818-4 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:95715 Serial 1503
Permanent link to this record
 

 
Author Kelchtermans, A.; Adriaensens, P.; Slocombe, D.; Kuznetsov, V.L.; Hadermann, J.; Riskin, A.; Elen, K.; Edwards, P.P.; Hardy, A.; Van Bael, M.K.
Title Increasing the solubility limit for tetrahedral aluminium in ZnO:Al nanorods by variation in synthesis parameters Type A1 Journal article
Year 2015 Publication Journal of nanomaterials Abbreviated Journal J Nanomater
Volume (up) 2015 Issue 2015 Pages 1-8
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Nanocrystalline ZnO:Al nanoparticles are suitable building blocks for transparent conductive layers. As the concentration of substitutional tetrahedral Al is an important factor for improving conductivity, here we aim to increase the fraction of substitutional Al. To this end, synthesis parameters of a solvothermal reaction yielding ZnO:Al nanorods were varied. A unique set of complementary techniques was combined to reveal the exact position of the aluminium ions in the ZnO lattice and demonstrated its importance in order to evaluate the potential of ZnO:Al nanocrystals as optimal building blocks for solution deposited transparent conductive oxide layers. Both an extension of the solvothermal reaction time and stirring during solvothermal treatment result in a higher total tetrahedral aluminium content in the ZnO lattice. However, only the longer solvothermal treatment effectively results in an increase of the substitutional positions aimed for.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000358516300001 Publication Date 2015-07-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1687-4110;1687-4129; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.871 Times cited 2 Open Access
Notes FWO; Methusalem Approved Most recent IF: 1.871; 2015 IF: 1.644
Call Number c:irua:124426 Serial 1600
Permanent link to this record
 

 
Author Nistor, L.C.; Richard, O.; Zhao, O.; Bender, H.; Stesmans, A.; Van Tendeloo, G.
Title A microstructural study of the thermal stability of atomic layer deposited Al2O3 thin films Type A1 Journal article
Year 2003 Publication Institute of physics conference series T2 – Microscopy of semiconducting materials Abbreviated Journal
Volume (up) Issue Pages 397-400
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The thermal stability of amorphous Al2O3 films (similar to8 and 80 nut thick) deposited by atomic layer deposition on HF-last and thin SiO2 covered (001) Si substrates is studied by transmission electron microscopy. The layers are in- and ex-situ annealed in the same temperature range.
Address
Corporate Author Thesis
Publisher Iop Place of Publication Cambridge Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0-7503-0979-2 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:54860 Serial 2048
Permanent link to this record
 

 
Author Verbist, K.; Tafuri, F.; Granozio, F.M.; Di Chiara, S.; Van Tendeloo, G.
Title Microstructure of artificial [100] 45 degrees twist grain boundaries in YBa2Cu3O7-delta Type P1 Proceeding
Year 1998 Publication Electron Microscopy 1998, Vol 2: Materials Science 1 Abbreviated Journal
Volume (up) Issue Pages 593-594
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000077019900291 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0-7503-0565-7 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:104356 Serial 2066
Permanent link to this record
 

 
Author Nikolaev, A.V.; Michel, K.H.
Title Molecular terms and optical transitions of C60n+/- molecular ions Type P1 Proceeding
Year 2002 Publication AIP conference proceedings T2 – 16th International Winterschool on Electronic Properties of Novel, Materials, MAR 02-09, 2002, KIRCHBERG, AUSTRIA Abbreviated Journal
Volume (up) Issue Pages 417-420
Keywords P1 Proceeding; Condensed Matter Theory (CMT)
Abstract We have studied the molecular energy terms of the hole configurations (h(u)(+))(m), m=2,3,4,5 of C-60(m+) cations and the electronic configurations (t(1u))(n) n=2,3,4, as well as (t(1u))(n-1)t(1g) of the C-60(n-) anions. The lowest terms (within an energy span of 0.03 eV) for C-60(2+) are three triplets T-3(1g), (3)G(g), T-3(2g) and for C-60(3+) are three quartets T-4(1u), (4)G(u), T-4(2u), which favor Jahn-Teller distortions. For the ground state of C-60(2-) we find a triplet T-3(1g) in agreement with Hund's rules. Our method takes into account intramolecular direct and exchange multipolar Coulomb interactions.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume 633 Series Issue Edition
ISSN 0-7354-0088-1 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:103905 Serial 2187
Permanent link to this record
 

 
Author Schryvers, D.; Ma, Y.; Toth, L.; Tanner, L.E.
Title Nucleation and growth of Ni5Al3 in austenite and martensite matrices Type P1 Proceeding
Year 1994 Publication Electron Microscopy 1994, Vols 2a And 2b: Applications In Materials Sciences Abbreviated Journal
Volume (up) Issue Pages 509-510
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1994BE09Y00247 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2-86883-226-1 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:104476 Serial 2386
Permanent link to this record
 

 
Author Nistor, L.; Van Tendeloo, G.; Amelinckx, S.; Shpanchenko, R.V.; van Landuyt, J.
Title Ordering and defects in BanTaxTiyO3n ternary oxides Type P1 Proceeding
Year 1994 Publication Electron Microscopy 1994, Vols 2a And 2b: Applications In Materials Sciences Abbreviated Journal
Volume (up) Issue Pages 869-870
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1994BE09Y00422 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2-86883-226-1 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:104477 Serial 2504
Permanent link to this record
 

 
Author Van Tendeloo, G.; Bernaerts, D.; Amelinckx, S.
Title Reduced dimensionality in different forms of carbon Type P1 Proceeding
Year 1998 Publication Fullerenes and carbon based materials Abbreviated Journal
Volume (up) Issue Pages 487-493
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract Several TEM techniques are used to characterise the local structure of low dimensional forms of carbon. HREM is particularly useful to describe the defect structure of thin films of diamond or fullerenes and C-60-C-70 nanoclusters. A columnar form of graphite is analysed, mainly by electron diffraction which allowed us to propose a growth mechanism. Diffraction contrast dark field microscopy, in combination with electron diffraction, allows a detailed characterisation of carbon nanotubes; e.g. the chirality distribution of tubes in ropes of single wall tubes is studied by selected area electron diffraction. (C) 1998 Elsevier Science Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000079731900002 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume 68 Series Issue Edition
ISSN 0-444-20512-8 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:104348 Serial 2850
Permanent link to this record
 

 
Author Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Warwick, M.E.A.; Kaunisto, K.; Sada, C.; Turner, S.; Gönüllü, Y.; Ruoko, T.-P.; Borgese, L.; Bontempi, E.; Van Tendeloo, G.; Lemmetyinen, H.; Mathur, S.
Title Fe2O3-TiO2Nano-heterostructure Photoanodes for Highly Efficient Solar Water Oxidation Type A1 Journal article
Year 2015 Publication Advanced Materials Interfaces Abbreviated Journal Adv Mater Interfaces
Volume (up) 2 Issue 2 Pages 1500313
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Harnessing solar energy for the production of clean hydrogen by photo­electrochemical water splitting represents a very attractive, but challenging approach for sustainable energy generation. In this regard, the fabrication of Fe2O3–TiO2 photoanodes is reported, showing attractive performances [≈2.0 mA cm−2 at 1.23 V vs. the reversible hydrogen electrode in 1 M NaOH] under simulated one-sun illumination. This goal, corresponding to a tenfold photoactivity enhancement with respect to bare Fe2O3, is achieved by atomic layer deposition of TiO2 over hematite (α-Fe2O3) nanostructures fabricated by plasma enhanced-chemical vapor deposition and final annealing at 650 °C. The adopted approach enables an intimate Fe2O3–TiO2 coupling, resulting in an electronic interplay at the Fe2O3/TiO2 interface. The reasons for the photocurrent enhancement determined by TiO2 overlayers with increasing thickness are unraveled by a detailed chemico-physical investigation, as well as by the study of photo­generated charge carrier dynamics. Transient absorption spectroscopy shows that the increased photoelectrochemical response of heterostructured photoanodes compared to bare hematite is due to an enhanced separation of photogenerated charge carriers and more favorable hole dynamics for water oxidation. The stable responses obtained even in simulated seawater provides a feasible route in view of the eventual large-scale generation of renewable energy.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000368914700011 Publication Date 2015-09-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2196-7350; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.279 Times cited 56 Open Access
Notes The authors kindly acknowledge the fi nancial support under the FP7 project “SOLAROGENIX” (NMP4-SL-2012-310333), as well as Padova University ex-60% 2012–2014 projects, Grant No. CPDR132937/13 (SOLLEONE), and Regione Lombardia-INSTM ATLANTE projects. S.T. acknowledges the FWO Flanders for a postdoctoral scholarship. Approved Most recent IF: 4.279; 2015 IF: NA
Call Number c:irua:129201 Serial 3957
Permanent link to this record
 

 
Author Djotyan, A.P.; Avetisyan, A.A.; Hao, Y.L.; Peeters, F.M.
Title Shallow donor near a semiconductor surface in the presence of locally spherical scanning tunneling microscope tip Type P1 Proceeding
Year 2012 Publication Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – Conference on Photonics and Micro and Nano-structured Materials, JUN 28-30, 2011, Yerevan, ARMENIA Abbreviated Journal
Volume (up) Issue Pages 84140-84148
Keywords P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We developed a variational approach to investigate the ground state energy and the extend of the wavefunction of a neutral donor located near a semiconductor surface in the presence of scanning tunneling microscope (STM) metallic tip. We apply the effective mass approximation and use a variational wavefunction that takes into account the influence of all image charges that arise due to the presence of a metallic tip. The behavior of the ground state energy when the tip approaches the semiconductor surface is investigated.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000303856600020 Publication Date 2012-01-20
Series Editor Series Title Abbreviated Series Title
Series Volume 8414 Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), and the Belgian Science Policy. One of us (AAA) was supported by a fellowship from the Belgian Federal Science Policy Office (Belspo). ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:113047 Serial 2987
Permanent link to this record
 

 
Author Lebedev, O.I.; Van Tendeloo, G.; Amelinckx, S.; Leibold, B.; Habermeier, H.U.; Phillipp, F.
Title Structure and magnetotransport properties of La2/3Ca1/3MnO3 thin films prepared by pulsed laser deposition Type P1 Proceeding
Year 1998 Publication Materials Research Society symposium proceedings T2 – Symposium on Advances in Laser Ablation of Materials at the 1998 MRS, Spring Meeting, April 13-16, 1998, San Francisco, Calif. Abbreviated Journal
Volume (up) Issue Pages 219-224
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract La1-xCaxMnO3-delta (LCMO) thin films are grown by pulsed laser deposition on a (100) SrTiO3 substrate at temperatures between 530 degrees C and 890 degrees C. The magnetotransport properties show a high negative magnetoresistance and a shift of the maximum of the R(T) curve as function of temperature. The Curie temperature changes with deposition temperature and film quality in the range of 100-220K. The film quality is characterised by X-ray diffraction and transmission electron microscopy (TEM); film and target compositions were verified by atomic emission spectroscopy. The local structure of the film depends on the growth conditions and substrate temperature. TEM reveals a slight distortion of the film leading to a breakdown of the symmetry from orthorhombic to monoclinic. At the highest growth temperatures, a well defined interface is observed within the LCMO film, parallel to the substrate surface; this interface divides the film into two lamellae with a different microstructure. The lamella close to the substrate is perfectly coherent with the substrate, suggesting that it is strained as a result of the lattice parameter mismatch; the upper lamella shows a typical domain structure with unusual translation interfaces characterised by a displacement vector of the type 1/2[010](m) and 1/2[001](m) when referred ten the monoclinic lattice.
Address
Corporate Author Thesis
Publisher Materials research society Place of Publication Warrendale Editor
Language Wos 000077696000032 Publication Date 2011-04-05
Series Editor Series Title Abbreviated Series Title
Series Volume 526 Series Issue Edition
ISSN 1946-4274; ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:95838 Serial 3283
Permanent link to this record
 

 
Author Fedotov, S.S.; Khasanova, N.R.; Samarin, A.S.; Drozhzhin, O.A.; Batuk, D.; Karakulina, O.M.; Hadermann, J.; Abakumov, A.M.; Antipov, E.V.
Title AVPO4F (A = Li, K): A 4 V Cathode Material for High-Power Rechargeable Batteries Type A1 Journal article
Year 2016 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume (up) 28 Issue 28 Pages 411-415
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A novel potassium-based fluoride-phosphate, KVPO4F, with a KTiOPO4 (KTP) type structure is synthesized and characterized. About 85% of potassium has been electrochemically extracted on oxidation producing a cathode material with attractive performance for Li-ion batteries. The material operates at the electrode potential near 4V vs Li/Li+ exhibiting a sloping voltage profile, extremely low polarization, small volume change of about 2% and excellent rate capability, maintaining more than 75% of the initial capacity at 40C discharge rate without significant fading.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000368949900002 Publication Date 2016-01-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 46 Open Access
Notes The authors kindly thank Dr. S. N. Putilin for XRD measurements, Dr. O. A. Shlyakhtin for the assistance in cryochemical synthesis, Ph.D. students A. A. Sadovnikov and E. A. Karpukhina for SEM imaging and FTIR spectra respectively. The work was partly supported by Russian Science Foundation (grant 16-19-00190), Skoltech Center for Electrochemical Energy Storage and Moscow State University Devel-opment Program up to 2020. J. Hadermann, O.M. Karakulina and A.M. Abakumov acknowledge support from FWO under grant G040116N. Approved Most recent IF: 9.466
Call Number c:irua:131583 Serial 4001
Permanent link to this record
 

 
Author Solmaz, A.; Huijben, M.; Koster, G.; Egoavil, R.; Gauquelin, N.; Van Tendeloo, G.; Verbeeck, J.; Noheda, B.; Rijnders, G.
Title Domain Selectivity in BiFeO3Thin Films by Modified Substrate Termination Type A1 Journal article
Year 2016 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume (up) 26 Issue 26 Pages 2882-2889
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Ferroelectric domain formation is an essential feature in ferroelectric thin films. These domains and domain walls can be manipulated depending on the growth conditions. In rhombohedral BiFeO3 thin films, the ordering of the domains and the presence of specific types of domain walls play a crucial role in attaining unique ferroelectric and magnetic properties. In this study, controlled ordering of domains in BiFeO3 film is presented, as well as a controlled selectivity between two types of domain walls is presented, i.e., 71° and 109°, by modifying the substrate termination. The experiments on two different substrates, namely SrTiO3 and TbScO3, strongly indicate that the domain selectivity is determined by the growth kinetics of the initial BiFeO3 layers.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000377587800011 Publication Date 2016-03-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1616-301X ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 34 Open Access
Notes The authors are grateful to Saeedeh Farokhipoor and Tamalika Banerjee for very useful discussions. This work was supported by the Netherlands Organization for Scientific Research NWO-FOM (under FOM-Nano project 10UNST04–2). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. GOA project “Solarpaint” of the University of Antwerp. The electron microscopy part of the work was supported by funding from the European Research Council under the 7th Framework Program (FP7), ERC Grant No. 246791– COUNTATOMS. Funding from the European Union Council under the 7th Framework Program (FP7) Grant No. NMP3-LA-2010–246102 FOX is acknowledged. The Fund for Scientific Research Flanders is acknowledged for FWO Project No. G.0044.13N. Approved Most recent IF: 12.124
Call Number c:irua:132641UA @ admin @ c:irua:132641 Serial 4053
Permanent link to this record
 

 
Author Lu, J.B.; Schryvers, D.
Title Microstructure and phase composition characterization in a Co38Ni33Al29 ferromagnetic shape memory alloy Type A1 Journal article
Year 2016 Publication Materials characterization Abbreviated Journal Mater Charact
Volume (up) 118 Issue 118 Pages 9-13
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Transmission electron microscopy was performed to investigate the microstructures of a secondary phase and its surrounding matrix in a Co38Ni33Al29 ferromagnetic shape memory alloy. The secondary phase shows a γ′ L12 structure exhibiting a dendritic morphology with enclosed B2 austenite regions while the matrix shows the L10 martensitic structure. A secondary phase-austenite-martensite sandwich structure with residual austenite ranging from several hundred nanometers to several micrometers wide is observed at the secondary phase-martensite interface due to the depletion of Co and enrichment of Al in the chemical gradient zone and the effect of the strong martensitic start temperature dependency of the element concentrations. The crystallographic orientation relationship of the secondary phase and the B2 austenite fits the Kurdjumov-Sachs relationship.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000383292000002 Publication Date 2016-05-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1044-5803 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.714 Times cited 3 Open Access
Notes J.B. Lu thanks the Belgian Science Ministry (Belspo) for support of his post-doctoral research stay at EMAT. We thank S. Sedlakova-Ignacova from the Institute of Physics in Prague, Czech Republic, for providing samples. Approved Most recent IF: 2.714
Call Number c:irua:133100 Serial 4071
Permanent link to this record
 

 
Author Serrano-Montes, A.B.; Langer, J.; Henriksen-Lacey, M.; Jimenez de Aberasturi, D.; Solís, D.M.; Taboada, J.M.; Obelleiro, F.; Sentosun, K.; Bals, S.; Bekdemir, A.; Stellacci, F.; Liz-Marzán, L.M.
Title Gold Nanostar-Coated Polystyrene Beads as Multifunctional Nanoprobes for SERS Bioimaging Type A1 Journal article
Year 2016 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume (up) 120 Issue 120 Pages 20860-20868
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Hybrid colloidal nanocomposites comprising polystyrene beads and plasmonic gold nanostars are reported as multifunctional optical nanoprobes. Such self-assembled structures are excellent Raman enhancers for bio-applications as they feature plasmon modes in the near infrared “first biological transparency window”. In this proof of concept study, we used 4- mercaptobenzoic acid as a Raman-active molecule to optimize the density of gold nanostars on polystyrene beads, improving SERS performance and thereby allowing in vitro cell culture imaging. Interestingly, intermediate gold nanostar loadings were found to yield higher SERS response, which was confirmed by electromagnetic modeling. These engineered hybrid nanostructures notably improve the possibilities of using gold nanostars as SERS tags. Additionally, when fluorescently labeled polystyrene bead are used as colloidal carriers, the composite particles can be applied as promising tools for multimodal bioimaging.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000384034600045 Publication Date 2016-05-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 64 Open Access OpenAccess
Notes Funding is acknowledged from the European Commission (Grant #310445-2 SAVVY), the European Research Council (ERC Advanced Grant #267867 Plasmaquo, and ERC Starting Grant #335078 Colouratom) and the Spanish MINECO (Project MAT2013-46101-R). We thank IKERLAT Polymers for the non-fluorescent PS beads and Prof. Juan Mareque, Prof. Soledad Penades and Dr. Sergio Moya (CIC biomagune) for borrowing various cell lines. D.M.S., J.M.T, and F.O. acknowledge funding from the European Regional Development Fund (ERDF) and the Spanish MINECO (Projects MAT2014-58201-C2-1-R, MAT2014- 58201-C2-2-R), from the ERDF and the Galician Regional Government under agreement for funding the Atlantic Research Center for Information and Communication Technologies (AtlantTIC), and from the ERDF and the Extremadura Regional Government (Junta de Extremadura) under Project IB13185. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ; ECAS_Sara; Approved Most recent IF: 4.536
Call Number c:irua:133952 Serial 4082
Permanent link to this record
 

 
Author De Keukeleere, K.; Cayado, P.; Meledin, A.; Vallès, F.; De Roo, J.; Rijckaert, H.; Pollefeyt, G.; Bruneel, E.; Palau, A.; Coll, M.; Ricart, S.; Van Tendeloo, G.; Puig, T.; Obradors, X.; Van Driessche, I.
Title Superconducting YBa2Cu3O7-δNanocomposites Using Preformed ZrO2Nanocrystals: Growth Mechanisms and Vortex Pinning Properties Type A1 Journal article
Year 2016 Publication Advanced Electronic Materials Abbreviated Journal
Volume (up) 2 Issue 2 Pages 1600161
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Although high temperature superconductors are promising for power applications, the production of low-cost coated conductors with high current densities—at high magnetic fields—remains challenging. A superior superconducting YBa2Cu3O7–δ nanocomposite is fabricated via chemical solution deposition (CSD) using preformed nanocrystals (NCs). Preformed, colloidally stable ZrO2 NCs are added to the trifluoroacetic acid based precursor solution and the NCs' stability is confirmed up to 50 mol% for at least 2.5 months. These NCs tend to disrupt the epitaxial growth of YBa2Cu3O7–δ, unless a thin seed layer is applied. A 10 mol% ZrO2 NC addition proved to be optimal, yielding a critical current density JC of 5 MA cm−2 at 77 K in self-field. Importantly, this new approach results in a smaller magnetic field decay of JC(H//c) for the nanocomposite compared to a pristine film. Furthermore, microstructural analysis of the YBa2Cu3O7–δ nanocomposite films reveals that different strain generation mechanisms may occur compared to the spontaneous segregation approach. Yet, the generated nanostrain in the YBa2Cu3O7–δ nanocomposite results in an improvement of the superconducting properties similar to the spontaneous segregation approach. This new approach, using preformed NCs in CSD coatings, can be of great potential for high magnetic field applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000386624100003 Publication Date 2016-09-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2199160X ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 26 Open Access
Notes This work was financially supported by a BOF research fund of Ghent University (BOF11/DOC/286), FWO Flanders (F08512), and Eurotapes, a collaborative project funded by the European Community’s Seven Framework Program (EU-FP7 NMP-LA-2012-280432). We also acknowledge MINECO and FEDER funds for MAT2014-51778-C2-1-R and the Center of Excellence award Severo Ochoa SEV-2015-0496, and SGR753 from the Generalitat of Catalunya. MC acknowledges RyC contract 2013-12448 Approved Most recent IF: NA
Call Number EMAT @ emat @ c:irua:135171 Serial 4118
Permanent link to this record
 

 
Author Ekimov, E.A.; Kudryavtsev, O.S.; Turner, S.; Korneychuk, S.; Sirotinkin, V.P.; Dolenko, T.A.; Vervald, A.M.; Vlasov, I.I.
Title The effect of molecular structure of organic compound on the direct high-pressure synthesis of boron-doped nanodiamond: Effect of organic compound on synthesis of boron-doped nanodiamond Type A1 Journal article
Year 2016 Publication Physica status solidi : A : applications and materials science Abbreviated Journal Phys Status Solidi A
Volume (up) 213 Issue 213 Pages 2582-2589
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Evolution of crystalline phases with temperature has been studied in materials produced by high-pressure high-temperature treatment of 9-borabicyclo[3.3.1]nonane dimer (9BBN), triphenylborane and trimesitylborane. The boron-doped diamond nanoparticles with a size below 10 nm were obtained at 8–9 GPa and temperatures 970–1250 °C from 9BBN only. Bridged structure and the presence of boron atom in the carbon cycle of 9BBN were revealed to be a key point for the direct synthesis of doped diamond nanocrystals. The diffusional transformation of the disordered carbon phase is suggested to be the main mechanism of the nanodiamond formation from 9BBN in the temperature range of 970–1400 °C. Aqueous suspensions of primary boron-doped diamond nanocrystals were prepared upon removal of non-diamond phases that opens wide opportunities for application of this new nanomaterial in electronics and biotechnologies.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000388321500006 Publication Date 2016-07-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6300 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.775 Times cited 8 Open Access
Notes Approved Most recent IF: 1.775
Call Number EMAT @ emat @ c:irua:135175 Serial 4120
Permanent link to this record
 

 
Author Gonnissen, J.; Batuk, D.; Nataf, G.F.; Jones, L.; Abakumov, A.M.; Van Aert, S.; Schryvers, D.; Salje, E.K.H.
Title Direct Observation of Ferroelectric Domain Walls in LiNbO3: Wall-Meanders, Kinks, and Local Electric Charges Type A1 Journal article
Year 2016 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume (up) 26 Issue 26 Pages 7599-7604
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Direct observations of the ferroelectric domain boundaries in LiNbO3 are performed using high-resolution high-angle annular dark field scanning transmission electron microscopy imaging, revealing a very narrow width of the domain wall between the 180° domains. The domain walls demonstrate local side-way meandering, which results in inclinations even when the overall wall orientation follows the ferroelectric polarization. These local meanders contain kinks with “head-to-head” and “tail-to-tail” dipolar configurations and are therefore locally charged. The charged meanders are confined to a few cation layers along the polarization direction and are separated by longer stretches of straight domain walls.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000388166700006 Publication Date 2016-09-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1616-301X ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 23 Open Access
Notes J.G. acknowledges the support from the Research Foundation Flanders (FWO, Belgium) through various project fundings (G.0368.15N, G.0369.15N, and G.0374.13N), as well as the financial support from the European Union Seventh Framework Program (FP7/2007–2013) under Grant agreement no. 312483 (ESTEEM2). The authors thank J. Hadermann for useful suggestions on the interpretation of the HAADFSTEM images. E.K.H.S. thanks the EPSRC (EP/K009702/1) and the Leverhulme Trust (EM-2016-004) for support. G.F.N. thanks the National Research Fund, Luxembourg (FNR/P12/4853155/Kreisel) for support.; esteem2_jra2 Approved Most recent IF: 12.124
Call Number c:irua:135336 c:irua:135336 Serial 4129
Permanent link to this record
 

 
Author Liao, Z.L.; Green, R.J.; Gauquelin, N.; Gonnissen, J.; Van Aert, S.; Verbeeck, J.; et al.
Title Engineering properties by long range symmetry propagation initiated at perovskite heterostructure interface Type A1 Journal article
Year 2016 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume (up) Issue Pages 1-25
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In epitaxial thin film systems, the crystal structure and its symmetry deviate from the bulk counterpart due to various mechanisms such as epitaxial strain and interfacial structural coupling, which induce an accompanying change in their properties. In perovskite materials, the crystal symmetry can be described by rotations of 6-fold coordinated transition metal oxygen octahedra, which are found to be altered at interfaces. Here, we unravel how the local oxygen octahedral coupling (OOC) at perovskite heterostructural interfaces initiates a different symmetry in epitaxial films and provide design rules to induce various symmetries in thin films by careful selecting appropriate combinations of substrate/buffer/film. Very interestingly we discovered that these combinations lead to symmetry changes throughout the full thickness of the film. Our results provide a deep insight into understanding the origin of induced crystal symmetry in a perovskite heterostructure and an intelligent route to achieve unique functional properties.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1616-301x ISBN Additional Links UA library record
Impact Factor 12.124 Times cited Open Access
Notes Approved Most recent IF: 12.124
Call Number UA @ lucian @ c:irua:134842 Serial 4176
Permanent link to this record
 

 
Author Conings, B.; Bretschneider, S.A.; Babayigit, A.; Gauquelin, N.; Cardinaletti, I.; Manca, J.V.; Verbeeck, J.; Snaith, H.J.; Boyen, H.-G.
Title Structure-property relations of methylamine vapor treated hybrid perovskite CH3NH3PbI3 films and solar cells Type A1 Journal article
Year 2017 Publication ACS applied materials and interfaces Abbreviated Journal Acs Appl Mater Inter
Volume (up) 9 Issue 9 Pages 8092-8099
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The power conversion efficiency of halide perovskite solar cells is heavily dependent on the perovskite layer being sufficiently smooth and pinhole-free. It has been shown that these features can be obtained even when starting out from rough and discontinuous perovskite film, by briefly exposing it to methylamine (MA) vapor. The exact underlying physical mechanisms of this phenomenon are, however, still unclear. By investigating smooth, MA treated films, based on very rough and discontinuous reference films of methylammonium triiode (MAPbI3), considering their morphology, crystalline features, local conductive properties, and charge carrier lifetime, we unravel the relation between their characteristic physical qualities and their performance in corresponding solar cells. We discover that the extensive improvement in photovoltaic performance upon MA treatment is a consequence of the induced morphological enhancement of the perovskite layer, together with improved electron injection into TiO2, which in fact compensates for an otherwise compromised bulk electronic quality, simultaneously caused by the MA treatment.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000396186000025 Publication Date 2017-02-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1944-8244 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.504 Times cited 43 Open Access OpenAccess
Notes This work was financially supported by BOF (Hasselt University) and the Research Fund Flanders (FWO). B.C. is a postdoctoral research fellow of the FWO. A.B. is financially supported by FWO and Imec. J.V. and N.G. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and FWO project G.0044.13N “Charge ordering”. The Qu-Ant-EM microscope used for this study was partly funded by the Hercules fund from the Flemish Government. The authors thank Tim Vangerven for Urbach energy determination, and Johnny Baccus and Jan Mertens for technical support. Approved Most recent IF: 7.504
Call Number EMAT @ emat @ c:irua:140849 Serial 4422
Permanent link to this record
 

 
Author Perez, A.J.; Batuk, D.; Saubanère, M.; Rousse, G.; Foix, D.; Mc Calla, E.; J. Berg, E.; Dugas, R.; van den Bos, K. H. W.; Doublet, M.-L.; Gonbeau, D.; Abakumov, A.M.; Van Tendeloo, G.; Tarascon, J.-M.
Title Strong oxygen participation in the redox governing the structural and electrochemical properties of Na-rich layered oxide Na2IrO3 Type A1 Journal article
Year 2016 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume (up) 28 Issue 28 Pages 8278-8288
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The recent revival of the Na-ion battery concept has prompted intense activities in the search for new Na-based layered oxide positive electrodes. The largest capacity to date was obtained for a Na-deficient layered oxide that relies on cationic redox processes only. To go beyond this limit, we decided to chemically manipulate these Na-based layered compounds in a way to trigger the participation of the anionic network. We herein report the electrochemical properties of a Na-rich phase Na2IrO3, which can reversibly cycle 1.5 Na+ per formula unit while not suffering from oxygen release nor cationic migrations. Such large capacities, as deduced by complementary XPS, X-ray/neutron diffraction and transmission electron microscopy measurements, arise from cumulative cationic and anionic redox processes occurring simultaneously at potentials as low as 3.0 V. The inability to remove more than 1.5 Na+ is rooted in the formation of an O1-type phase having highly stabilized Na sites as confirmed by DFT calculations, which could rationalize as well the competing metal/oxygen redox processes in Na2IrO3. This work will help to define the most fertile directions in the search for novel high energy Na-rich materials based on more sustainable elements than Ir.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000388914500021 Publication Date 2016-10-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 45 Open Access
Notes The authors thank Montse Casas-Cabanas and Marine Reynaud for discussions about the FAULTS program, Sandra Van Aert for her great help in guiding us towards the use of the statistical parameter estimation method for establishing the O-O histogram, and Thomas Hansen and Vladimir Pomjakushin for their precious help in neutron diffraction experiments. This work is based on experiments performed at the Swiss spallation neutron source SINQ, Paul Scherrer Institute, Villigen, Switzerland, and at Institut Laue Langevin, Grenoble, France. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the U.S. department of Energy under contract No. DE-AC02-06CH11357 and is greatly acknowledged. Approved Most recent IF: 9.466
Call Number EMAT @ emat @ c:irua:135994 Serial 4287
Permanent link to this record