Thermochromic vanadium oxide thin films: Electronic and optical properties

INERA Workshop: Transition Metal Oxide Thin Films-functional Layers in "Smart windows" and Water Splitting Devices

Niklasson, G.A.^1 ; Li, S.-Y.^1 ; Granqvist, C.G.^1

Department of Engineering Sciences, Ångström Laboratory, Uppsala University, Uppsala, Sweden^1

关键词: Critical temperatures;    Crystal structure transformation;    Electronic and optical properties;    Energy-efficient windows;    Metal-to-insulator transitions;    Thermochromic materials;    Transparent matrix;    Vanadium oxide thin films;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/559/1/012001/pdf
DOI  :  10.1088/1742-6596/559/1/012001

来源: IOP

【 摘 要 】

Vanadium dioxide, VO2, is a widely studied thermochromic material with potential applications in energy efficient window technology. It undergoes a first-order metal-to- insulator transition, accompanied by a crystal structure transformation from monoclinic to tetragonal rutile, at a critical temperature of 68 °C. Below this temperature, VO2is semiconducting and infrared transmitting whereas it is metallic and infrared reflecting above the transition temperature. However, in order to achieve significant thermochromic switching, the luminous transmittance of thin films will typically be less than 50%. Here we report on recent research to improve the luminous transmittance as well as the transmittance change at the transition temperature. We systematically evaluate the effect of antireflection coatings, doping with Mg and the performance of coatings comprising thermochromic nanoparticles in a transparent matrix. The last option is shown to give the best performance and holds great promise for practical applications.