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

We report on high-performance thermochromic ZrO/VWO/ZrO coatings with a low transition temperature prepared on glass by a low-temperature scalable deposition technique. The VWO 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. ZrO antireflection layers both below and above the thermochromic VWO layers were deposited at a low substrate temperature (< 100 °C). A coating design utilizing a second-order interference in the ZrO layers was applied to increase both the luminous transmittance (T) and the modulation of the solar transmittance (ΔT). The ZrO/VWO/ZrO coatings exhibit T up to 60% at ΔT close to 6% for a VWO thickness of 45 nm, and T up to 50% at ΔT above 10% for a VWO thickness of 69 nm.