Ultrafast coloring-bleaching performance of nanoporous WO ₃-SiO ₂ gasochromic films doped with Pd catalyst

Figure Presented: The gasochromic performance and durability of WO ₃-based films can be improved by doping SiO ₂ particles within WO ₃ matrix forming nanoporous supporting network and dispersing Pd catalyst inside films with enhanced catalytic activity. Nanoporous WO ₃-SiO ₂ composite films loaded with Pd catalyst were prepared by sol-gel dip-coating process and served as an active chromogenic layer to fabricate a double-glazed gasochromic device. The structure, morphology, optical properties and gasochromic performance of WO ₃-SiO ₂ films were fully investigated. The WO ₃-SiO ₂ films exhibit excellent gasochromic performance with ultrafast coloring rate of 14.8% per second (%/s) (WO ₃: 2.84%/s) and bleaching rate of 44.1%/s (WO ₃: 7.18%/s). The transmittance changed between 17.8 and 74.6% during coloring-bleaching cycles, and totally reversibility and stability were achieved.