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arXiv · 2301.00634

Non-Equilibrium Spark Plasma Reactive Doping Enables Highly Adjustable Metal to Insulator Transitions and Improved Mechanical Stability for VO2

Xuanchi Zhou·Yuchen Cui·Yanlong Shang·Haifan Li·Jiaou Wang·Ye Meng·Xiaoguang Xu·Yong Jiang·Nuofu Chen·Jikun Chen
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Abstract

Although vanadium dioxide (VO2) exhibits the most abrupt metal to insulator transition (MIT) properties near room-temperature, the present regulation of their MIT functionalities is insufficient owing to the high complexity and susception associated with V4+. Herein, we demonstrate a spark plasma assisted reactive sintering (SPARS) approach to simultaneously achieve in situ doping and sintering of VO2 within largely short period (~10 minutes). This enables high convenience and flexibility in regulating the electronic structure of VO2 via dopant elements covering Ti, W, Nb, Mo, Cr and Fe, leading to a wide adjustment in their metal to insulator transition temperature (TMIT) and basic resistivity. Furthermore, the mechanical strengths of the doped-VO2 were meanwhile largely improved via the compositing effect of high melting-point dopant oxide. The high adjustability in MIT properties and improved mechanical properties further paves the way towards practical applications of VO2 in power electronics, thermochromism and infrared camouflage.

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Xuanchi Zhou, Yuchen Cui, Yanlong Shang, Haifan Li, Jiaou Wang, Ye Meng, Xiaoguang Xu, Yong Jiang, Nuofu Chen, Jikun Chen. 2023-01-02. Non-Equilibrium Spark Plasma Reactive Doping Enables Highly Adjustable Metal to Insulator Transitions and Improved Mechanical Stability for VO2. https://arxiv.org/abs/2301.00634

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