Tuning Phase Transition and Thermochromic Properties of Vanadium Dioxide Thin Films via Cobalt Doping

Authors

Xun Geng, UNSW Sydney
Tianci Chang, Shanghai Institute of Ceramics Chinese Academy of Sciences
Jiaxin Fan, UNSW Sydney
Yu Wang, UNSW Sydney
Xiaotian Wang, University of Wollongong
Yunlong Sun, UNSW Sydney
Premkumar Selvarajan, The University of Newcastle, Australia
Chuang Liu, UNSW Sydney
Chun Ho Lin, UNSW Sydney
Xiaolin Wang, University of Wollongong
Jack Yang, UNSW Sydney
Zhenxiang Cheng, University of Wollongong
Kourosh Kalantar-Zadeh, UNSW Sydney
Xun Cao, Shanghai Institute of Ceramics Chinese Academy of Sciences
Danyang Wang, UNSW Sydney
Ajayan Vinu, The University of Newcastle, Australia
Jiabao Yi, The University of Newcastle, Australia
Tom Wu, UNSW Sydney

Publication Name

ACS Applied Materials and Interfaces

Abstract

Vanadium dioxide (VO2) featuring a distinct thermally triggered phase transition is regarded as the most attractive thermochromic material for smart window applications. However, the high transition temperature (∼67 °C) and moderate luminous transmittance (<50%) of the pristine VO2 circumvent room temperature applications. In this work, epitaxial cobalt-doped VO2 thin films were fabricated to tailor the electric and optical properties on a c-plane sapphire substrate. At the highest doping concentration of 10%, the transition temperature of VO2 is reduced to 44 °C, accompanied by a high luminous transmittance of 79% for single-element Co-doped VO2. The roles of cobalt doping and detailed band variation are fully explained experimentally and by modeling (DFT calculation), respectively. Furthermore, the dramatically increased carrier concentration in cobalt-doped VO2 underscores the promising future of cobalt-doped VO2 unveiled by temperature-dependent Hall effect measurement.

Open Access Status

This publication is not available as open access

Funding Number

DP190103316

Funding Sponsor

Australian Research Council