|
Records |
Links |
|
Author |
Liang, Q.; Yang, D.; Xia, F.; Bai, H.; Peng, H.; Yu, R.; Yan, Y.; He, D.; Cao, S.; Van Tendeloo, G.; Li, G.; Zhang, Q.; Tang, X.; Wu, J. |
|
|
Title |
Phase-transformation-induced giant deformation in thermoelectric Ag₂Se semiconductor |
Type |
A1 Journal article |
|
Year |
2021 |
Publication |
Advanced Functional Materials |
Abbreviated Journal |
Adv Funct Mater |
|
|
Volume |
|
Issue |
|
Pages |
2106938 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
In most semiconducting metal chalcogenides, a large deformation is usually accompanied by a phase transformation, while the deformation mechanism remains largely unexplored. Herein, a phase-transformation-induced deformation in Ag2Se is investigated by in situ transmission electron microscopy, and a new ordered high-temperature phase (named as alpha '-Ag2Se) is identified. The Se-Se bonds are folded when the Ag+-ion vacancies are ordered and become stretched when these vacancies are disordered. Such a stretch/fold of the Se-Se bonds enables a fast and large deformation occurring during the phase transition. Meanwhile, the different Se-Se bonding states in alpha-, alpha '-, beta-Ag2Se phases lead to the formation of a large number of nanoslabs and the high concentration of dislocations at the interface, which flexibly accommodate the strain caused by the phase transformation. This study reveals the atomic mechanism of the deformation in Ag2Se inorganic semiconductors during the phase transition, which also provides inspiration for understanding the phase transition process in other functional materials. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000695142800001 |
Publication Date |
2021-09-13 |
|
|
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 |
|
Open Access |
Not_Open_Access |
|
|
Notes |
|
Approved |
Most recent IF: 12.124 |
|
|
Call Number |
UA @ admin @ c:irua:181527 |
Serial |
6879 |
|
Permanent link to this record |
|
|
|
|
Author |
Guo, A.; Bai, H.; Liang, Q.; Feng, L.; Su, X.; Van Tendeloo, G.; Wu, J. |
|
|
Title |
Resistive switching in Ag₂Te semiconductor modulated by Ag+-ion diffusion and phase transition |
Type |
A1 Journal article |
|
Year |
2022 |
Publication |
Advanced Electronic Materials |
Abbreviated Journal |
Adv Electron Mater |
|
|
Volume |
|
Issue |
|
Pages |
2200850-2200858 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Memristors are considered to be the fourth circuit element and have great potential in areas like logic operations, information storage, and neuromorphic computing. The functional material in a memristor, which has a nonlinear resistance, is the key component to be developed. Herein, resistive switching is demonstrated and the structural evolutions in Ag2Te are examined under an external electric field. It is shown that the electroresistance effect is originating from an electronically triggered phase transition together with directional Ag+-ion diffusion. Using in situ transmission electron microscopy, the phase transition from the monoclinic alpha-Ag2Te into the face-centered cubic beta-Ag2Te, accompanied by a change in resistance, is directly observed. Diffusion of Ag+-ions modulates the localized density of Ag+-ion vacancies, leading to a change in electrical conductivity and influences the threshold voltage to trigger the phase transition. During the electric field-driven phase transition, the spontaneous and localized multiple polarizations from the low-symmetry alpha-Ag2Te (referring to an antiferroelectric structure) are vanishing in the cubic beta-Ag2Te (referring to a paraelectric structure). The abrupt resistance change of thin Ag2Te caused by the phase transition and modulated by the applied electric field demonstrates its great potential as functional material in volatile memory and memristors with a low-energy consumption. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000855728500001 |
Publication Date |
2022-09-21 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2199-160x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
6.2 |
Times cited |
|
Open Access |
Not_Open_Access |
|
|
Notes |
|
Approved |
Most recent IF: 6.2 |
|
|
Call Number |
UA @ admin @ c:irua:190582 |
Serial |
7203 |
|
Permanent link to this record |
|
|
|
|
Author |
Wang, G.; Xie, C.; Wang, H.; Li, Q.; Xia, F.; Zeng, W.; Peng, H.; Van Tendeloo, G.; Tan, G.; Tian, J.; Wu, J. |
|
|
Title |
Mitigated oxygen loss in lithium-rich manganese-based cathode enabled by strong Zr-O affinity |
Type |
A1 Journal article |
|
Year |
2024 |
Publication |
Advanced functional materials |
Abbreviated Journal |
|
|
|
Volume |
|
Issue |
|
Pages |
2313672 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Oxygen loss is a serious problem of lithium-rich layered oxide (LLO) cathodes, as the high capacity of LLO relies on reversible oxygen redox. Oxygen release can occur at the surface leading to the formation of spinel or rock salt structures. Also, the lattice oxygen will usually become unstable after long cycling, which remains a major roadblock in the application of LLO. Here, it is shown that Zr doping is an effective strategy to retain lattice oxygen in LLO due to the high affinity between Zr and O. A simple sol-gel method is used to dope Zr4+ into the LLOs to adjust the local electronic structure and inhibit the diffusion of oxygen anions to the surface during cycling. Compared with untreated LLOs, LLO-Zr cathodes exhibit a higher cycling stability, with 94% capacity retention after 100 cycles at 0.4 C, up to 223 mAh g-1 at 1 C, and 88% capacity retention after 300 cycles. Theoretical calculations show that due to the strong Zr-O covalent bonding, the formation energy of oxygen vacancies has effectively increased and the loss of lattice oxygen under high voltage can be suppressed. This study provides a simple method for developing high-capacity and cyclability Li-rich cathode materials for lithium-ion batteries. Oxygen release can occur at the cathode surface leading to the formation of spinel or rock salt structures. Here, it is shown that Zr doping is an effective strategy to retain lattice oxygen in lithium-rich layered oxides (LLO) due to the high affinity between Zr and O. LLO-Zr exhibit higher cycling stability, with 88% capacity retention after 300 cycles at 1 C. image |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
001159843800001 |
Publication Date |
2024-02-10 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
|
Impact Factor |
19 |
Times cited |
|
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 19; 2024 IF: 12.124 |
|
|
Call Number |
UA @ admin @ c:irua:203812 |
Serial |
9161 |
|
Permanent link to this record |
|
|
|
|
Author |
Sieger, M.; Pahlke, P.; Lao, M.; Eisterer, M.; Meledin, A.; Van Tendeloo, G.; Ottolinger, R.; Haenisch, J.; Holzapfel, B.; Usoskin, A.; Kursumovic, A.; MacManus-Driscoll, J.L.; Stafford, B.H.; Bauer, M.; Nielsch, K.; Schultz, L.; Huehne, R. |
|
|
Title |
Tailoring microstructure and superconducting properties in thick BaHfO3 and Ba2YNb/Ta)O-6 doped YBCO films on technical templates |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
IEEE transactions on applied superconductivity |
Abbreviated Journal |
|
|
|
Volume |
27 |
Issue |
4 |
Pages |
6601407 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
The current transport capability of YBa2Cu3O7-x(YBCO) based coated conductors (CCs) is mainly limited by two features: the grain boundaries of the used textured template, which are transferred into the superconducting film through the buffer layers, and the ability to pin magnetic flux lines by incorporation of defined defects in the crystal lattice. By adjusting the deposition conditions, it is possible to tailor the pinning landscape in doped YBCO in order to meet specific working conditions (T, B) for CC applications. To study these effects, we deposited YBCO layers with a thickness of about 1-2 mu m using pulsed laser deposition on buffered rolling-assisted biaxially textured Ni-W substrates as well as on metal tapes having either an ion-beam-texturedYSZbuffer or an MgO layer textured by inclined substrate deposition. BaHfO3 and the mixed double-perovskite Ba2Y(Nb/Ta)O-6 were incorporated as artificial pinning centers in these YBCO layers. X-ray diffraction confirmed the epitaxial growth of the superconductor on these templates as well as the biaxially oriented incorporation of the secondary phase additions in the YBCO matrix. A critical current density J(c) of more than 2 MA/cm(2) was achieved at 77 K in self-field for 1-2 mu m thick films. Detailed TEM (transmission electron microscopy) studies revealed that the structure of the secondary phase can be tuned, forming c-axis aligned nanocolumns, ab-oriented platelets, or a combination of both. Transport measurements show that the J(c) anisotropy in magnetic fields is reduced by doping and the peak in the J(c) (theta) curves can be correlated to the microstructural features. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000394588100001 |
Publication Date |
2016-12-24 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1051-8223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
|
Times cited |
12 |
Open Access |
OpenAccess |
|
|
Notes |
; This work was supported by EUROTAPES, a collaborative project funded by the European Commission's Seventh Framework Program (FP7/2007-2013) under Grant Agreement no. 280432. ; |
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ lucian @ c:irua:141961 |
Serial |
4693 |
|
Permanent link to this record |
|
|
|
|
Author |
Roxana Vlad, V.; Bartolome, E.; Vilardell, M.; Calleja, A.; Meledin, A.; Obradors, X.; Puig, T.; Ricart, S.; Van Tendeloo, G.; Usoskin, A.; Lee, S.; Petrykin, V.; Molodyk, A. |
|
|
Title |
Inkjet printing multideposited YBCO on CGO/LMO/MgO/Y2O3/Al2O3/Hastelloy tape for 2G-coated conductors |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
IEEE transactions on applied superconductivity |
Abbreviated Journal |
|
|
|
Volume |
28 |
Issue |
4 |
Pages |
6601805 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
We present the preparation of a new architecture of coated conductor by Inkjet printing of low fluorine YBa2Cu3O7-x (YBCO) on top of SuperOx tape: CGO/LMO/IBAD-MgO/Y2O3/Al-2 O-3/Hastelloy. A five-layered multideposited, 475-nm-thick YBCO film was structurally and magnetically characterized. A good texture was achieved using this combination of buffer layers, requiring only a 30-nm-thin ion-beam-assisted deposition (IBAD)-MgO layer. The LF-YBCO CC reaches self-field critical current density values of J(c)(GB) similar to NJ 15.9 MA/cm(2) (5 K), similar to 1.23 MA/cm(2) (77 K) corresponding to an I-c (77 K) = 58.4 A/cm-width. Inkjet printing offers a flexible and cost effective method for YBCO deposition, allowing patterning of structures. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000429010900001 |
Publication Date |
2018-02-22 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1051-8223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.288 |
Times cited |
2 |
Open Access |
Not_Open_Access |
|
|
Notes |
; This work was performed within the framework of the EUROTAPES Project FP7-NMP.2011.2.2-1 under Grant280432, funded by the EU. ICMAB research was financed by the Ministry of Economy and Competitiveness, and FEDER funds under Projects MAT2011-28874-C02-01, MAT2014-51778-C2-1-R, ENE2014-56109-C3-3-R, and Consolider Nanoselect CSD2007-00041, and by Generalitat de Catalunya (2009 SGR 770, 2015 SGR 753, and Xarmae). ICMAB acknowledges support from Severo Ochoa Program (MINECO) under Grant SEV-2015-0496. ; |
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ lucian @ c:irua:150711 |
Serial |
4971 |
|
Permanent link to this record |
|
|
|
|
Author |
Sieger, M.; Pahlke, P.; Lao, M.; Meledin, A.; Eisterer, M.; Van Tendeloo, G.; Schultz, L.; Nielsch, K.; Huehne, R. |
|
|
Title |
Thick secondary phase pinning-enhanced YBCO films on technical templates |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
IEEE transactions on applied superconductivity |
Abbreviated Journal |
|
|
|
Volume |
28 |
Issue |
4 |
Pages |
8000505 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
The critical current I-c(B) of YBa2Cu3O7-delta (YBCO) coated conductors can be increased by growing thicker superconductor layers as well as improving the critical current density J(c)(B) by the incorporation of artificial pinning centers. We studied the properties of pulsed laser deposited BaHfO3 (BHO)-doped YBCO films with thicknesses of up to 5 mu m on buffered rolling-assisted biaxially textured Ni-5 at % W tape and alternating beam assisted deposition textured Yttrium-stabilized ZrO2 layers on stainless steel. X-Ray diffraction confirms the epitaxial growth of the superconductor on the buffered metallic template. BHO additions reduce the film porosity and lower the probability to grow misoriented grains, hence preventing the J(c) decrease observed in undoped YBCO films with thicknesses > 2 mu m. Thereby, a continuous increase in I-c at 77 K is achieved. A mixed structure of secondary phase nanorods and platelets with different orientations increases J(c)(B) in the full angular range and simultaneously lowers the J(c) anisotropy compared to pristine YBCO. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000427623700001 |
Publication Date |
2018-01-30 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1051-8223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.288 |
Times cited |
1 |
Open Access |
Not_Open_Access |
|
|
Notes |
; This work was supported by EUROTAPES, a collaborative project funded by the European Commission's Seventh Framework Program (FP7 / 2007 – 2013) under Grant Agreement no. 280432. Max Sieger acknowledges funding by the Graduate Academy of the Technical University Dresden, funded by means of the Excellence Initiative by the German Federal and State Governments. ; |
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ lucian @ c:irua:150712 |
Serial |
4986 |
|
Permanent link to this record |