High-performance thermochromic VO2-based coatings with a low transition temperature deposited on glass by a scalable technique

Abstract

We report on high-performance thermochromic ZrO2/V0.982W0.018O2/ZrO2 coatings with a low transition temperature prepared on glass by a low-temperature scalable deposition technique. The V0.982W0.018O2 layers were deposited by a controlled high-power impulse magnetron sputtering of V target, combined with a simultaneous pulsed DC magnetron sputtering of W target to reduce the transition temperature to 20–21 °C, at a low substrate surface temperature of 330 °C in an argon–oxygen gas mixture. ZrO2 antireflection layers both below and above the thermochromic V0.982W0.018O2 layers were deposited at a low substrate temperature (< 100 °C). A coating design utilizing a second-order interference in the ZrO2 layers was applied to increase both the luminous transmittance (Tlum) and the modulation of the solar transmittance (ΔTsol). The ZrO2/V0.982W0.018O2/ZrO2 coatings exhibit Tlum up to 60% at ΔTsol close to 6% for a V0.982W0.018O2 thickness of 45 nm, and Tlum up to 50% at ΔTsol above 10% for a V0.982W0.018O2 thickness of 69 nm.