Optimized Atmospheric-Pressure Chemical Vapor Deposition Thermochromic VO2 Thin Films for Intelligent Window Applications

Delphine Malarde; Michael J Powell; Raul Quesada-Cabrera; Rachel L Wilson; Claire J Carmalt; Gopinathan Sankar; Ivan P Parkin; Robert G Palgrave

doi:10.1021/acsomega.7b00042

Optimized Atmospheric-Pressure Chemical Vapor Deposition Thermochromic VO₂ Thin Films for Intelligent Window Applications

ACS Omega. 2017 Mar 20;2(3):1040-1046. doi: 10.1021/acsomega.7b00042. eCollection 2017 Mar 31.

Authors

Delphine Malarde¹, Michael J Powell¹, Raul Quesada-Cabrera¹, Rachel L Wilson¹, Claire J Carmalt¹, Gopinathan Sankar¹, Ivan P Parkin¹, Robert G Palgrave¹

Affiliation

¹ Department of Chemistry, Materials Chemistry Centre, University College London, 20 Gordon Street, London WC1H 0AJ, U.K.

Abstract

Monoclinic vanadium(IV) oxide (VO₂) has been widely studied for energy-efficient glazing applications because of its thermochromic properties, displaying a large change in transmission of near-IR wavelengths between the hot and cold states. The optimization of the reaction between VCl₄ and ethyl acetate via atmospheric-pressure chemical vapor deposition (APCVD) was shown to produce thin films of monoclinic VO₂ with excellent thermochromic properties (ΔT _sol = 12%). The tailoring of the thermochromic and visible light transmission was shown to be possible by altering the density and morphology of the deposited films. The films were characterized by X-ray diffraction, atomic-force microscopy, scanning electron microscopy, ellipsometry, and UV-vis spectrometry. This article provides useful design rules for the synthesis of high-quality VO₂ thin films by APCVD.