Electrochromic properties of WO3 thin film onto gold nanoparticles modified indium tin oxide electrodes

► Gold nanoparticle (GNP) thin films were electrodeposited onto indium tin oxide coated glass. ► The color of GNP film can vary from pale red to blue. ► The WO3/GNPs composite films were fabricated by sol-gel method. ► Their electrochromic performance was improved in comparison with a single component system of WO3.