Structural and electrochromic properties of sol-gel made tantalum oxide and tungsten oxide films

Tantalum oxide and tungsten oxide thin films were prepared by spin coating techniques. The effect of tantalum concentration on the optical, structural and electrochromic properties of the films were studied. The optical, structural and electrochromic properties of pure, WO₃, Ta₂O₅ and Ta₂O₅ doped WO₃ thin films are described and compared to each other. Film characterization was made by cyclic voltammetry (CV) and scanning electron microscopy (SEM). The coatings were studied electrochemically in 1 M LiClO₄ in propylene carbonate electrolytes. Electrochemical and optical characterizations show that the tantalum concentration affects the properties of sol-gel derived films significantly. Mechanical tests show that tantalum oxide films resist to abrasion well.