Versatility of various tungsten oxide nanostructures towards fostering electrochromic state of the art: a review

Electrochromism is the process of changing a material’s optical glaze from coloured to bleached and vice versa by applying a reversible voltage. It is worth noting that across all transition metal oxides, tungsten oxide (WO3) has acquired a prime focus owing to its versatile electrochromic properties. High coloration efficiency, high diffusion coefficient (D), high cyclic stability, high optical modulation, and fast switching time are few properties which makes WO3, a versatile electrochromic material. Over the years, many scientists and researchers have been encouraged to extravagant their work on WO3, to realise its hidden electrochromic persona. Various nanostructured forms of WO3 have been studied till now. Every form of WO3 film defines a different electrochromic capability. In this review we try to portray versatility of various nanostructured forms of WO3 such as nanowires, nanorods, nanotrees, nanoflowers, nanoflakes, and nanoporous films towards acquiring electrochromic state of the art.