Facile and dynamic infrared modulation of durable VO₂/CuI films for smart window applications

Vanadium dioxide (VO₂) has been widely investigated as a smart window material due to its excellent thermochromic properties. However, with the increasing abundance of studies on VO₂-based structures, its low solar modulation capability, environmental durability and high phase transition temperature have limited its commercial applications. Finding a simple way to solve the above problems simultaneously remains challenging. Here, we propose a bilayer structure combining VO₂ and a transparent conductive material, copper iodide (CuI), for functional integration of thermochromic smart windows. The CuI layer is used as an anti-reflective layer and a protective layer to ensure high solar modulation capability (ΔT_sol=15.41 %) and good expected service life (ESL=27 years), while realizing the dynamic modulation of infrared spectra at room temperature by Joule heating. This facile structure with overall performance offers a new possibility for the commercialization of VO₂-based smart windows and room temperature dynamic modulation of infrared devices.