Used as a catalyst in chemical synthesis, particularly in oxidation reactions, due to its mixed valence states which enhance redox activity. Commonly applied in the production of sulfuric acid and selective catalytic reduction of nitrogen oxides. Also explored in energy storage systems, such as vanadium redox flow batteries, where it contributes to efficient charge and discharge cycles. Shows potential in electrochromic devices for smart windows because of its ability to change optical properties with applied voltage.