Broadband-modulated Photochromic Smart Windows Based on Oxygen-containing Gadolinium Hydride Films

Photochromic materials show promise as effective photo-thermal modulators due to their simple structure, ability to passively modulate light, and zero energy input.Harnessing the potential of photochromic smart windows for dynamic sunlight control holds significant potential in reducing building energy consumption and improving occupant comfort.Additionally, dynamic radiant cooling (DRC) technology has emerged as a robust solution for building thermal management.By dynamically adjusting the material surface emissivity to selectively emit Mid-infrared (MIR) rays into the cold outer space, DRC provides effective cooling in hot weather and insulation in cold conditions.Integrating photochromic materials with dynamic radiative cooling properties has the potential to push the boundaries of energy savings.In this study, we explored the capabilities of rare-earth oxygen-containing hydrides (ReOxHy) for broadband modulation applications, discussing the preparation atmosphere of GdOxHy, and analyzing its photochromism mechanism through comprehensive characterization.The developed photochromic smart window is capable of automatically adjusting emissivity by sensing light intensity while maintaining visible and near-infrared (NIR) modulation.This passive and synergistic modulation across the visible-NIR-LWIR spectrum (ΔTsol=35.1%,ΔTlum=37%, and Δε8-13 μm=0.12)showcased by this innovative window holds the promise of significantly advancing the field of photochromic smart windows.