Impurity‐Induced First‐Order Phase Transitions in Highly Crystalline V2O3 Nanocrystals
Source abstract
Abstract
A first‐order phase transition in a bulk material is generally considered to arise at extended defects such as grain boundaries or dislocations, where the energetic barrier between the two phases is reduced. Downsizing a crystal to the nanoscale can exclude the number of defects, leading to enhanced kinetic stabilization of the metastable phase. Here, the disappearance of the first‐order metal–insulator transition in defect‐free V2O3 nanocrystals and the revival of the transition by introducing a certain Cr or Ti impurity content are investigated. The hysteresis width of the transition corresponding to the barrier height decreases with the impurity content. It is proposed that homogeneous impurity doping is a universal method that can control the occurrence of a first‐order phase transition in nanoscale materials.
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Research context
OpenAlex topics: Transition Metal Oxide Nanomaterials · Catalysis and Oxidation Reactions · Gas Sensing Nanomaterials and Sensors
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Physics Saga University 1 Honjo Saga 840‐8502 Japan
Synchrotron Light Application Center Saga University 1 Honjo Saga 840‐8502 Japan
National Synchrotron Radiation Research Center 101 Hsin‐Ann Road, Hsinchu Science Park Hsinchu 30076 Taiwan
Department of Advanced Physics Hirosaki University 3, Bunkyo, ‐cho Hirosaki 036‐8561 Japan
Department of Applied Quantum Physics Kyushu University 744 Motooka Nishi‐ku, Fukuoka 819‐0395 Japan
Institute for Solid State Physics University of Tokyo 5‐1‐5 Kashiwanoha Kashiwa, Chiba 277‐8581 Japan
Advanced Device Laboratory RIKEN 2‐1 Hirosawa Wako 351‐0198 Japan
CEMS RIKEN 2‐1 Hirosawa Wako 351‐0198 Japan
Department of Applied Chemistry and Biochemistry Kumamoto University 2‐39‐1 Kurokami Chuo‐ku, Kumamoto 860‐8555 Japan
References (33)
Show source-provided references
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21. Another nondopd sample showed a faint change inχ accompanied with an extremely wide hysteresis loop as shown in Figure S3 (Supporting Information). The appearance of the change may be derived from a certain difference in the surface region or the crystallinity. The faint change inχhas been observed only for the one sample among the total five samples which we synthesized on nondoped or dilute Cr‐doped NCs with sizes of 30–50 nm.
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