|   | 
Details
   web
Records
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 (up) 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 Yu, R.; Zeng, W.; Zhou, L.; Van Tendeloo, G.; Mai, L.; Yao, Z.; Wu, J.
Title Layer-by-layer delithiation during lattice collapse as the origin of planar gliding and microcracking in Ni-rich cathodes Type A1 Journal article
Year (up) 2023 Publication Cell reports physical science Abbreviated Journal
Volume 4 Issue 7 Pages 101480-14
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract High-energy-density nickel (Ni)-rich cathode materials are used in commercial lithium (Li)-ion batteries for electric vehicles, but they suffer from severe structural degradation upon cycling. Planar gliding and microcracking are seeds for fatal mechanical fracture, but their origin remains unclear. Herein, we show that “layer-by -layer delithiation”is activated at high voltages during the charge process when the “lattice collapse”(a characteristic high-voltage lattice evolution in Ni-rich cathodes) occurs. Layer-by-layer deli-thiation is evidenced by direct observation of the consecutive lattice collapse using in situ scanning transmission electron micro-scopy (STEM). The collapsing of the lattice initiates in the expanded planes and consecutively extends to the whole crystal. Localized strain will be induced at lattice-collapsing interface where planar gliding and intragranular microcracks are generated to release this strain. Our study reveals that layer-by-layer delithia-tion during lattice collapse is the fundamental origin of the mechanical instability in single-crystalline Ni-rich cathodes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001048074500001 Publication Date 2023-06-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:198299 Serial 8893
Permanent link to this record