Binder-free room-temperature synthesis of amorphous-WO3 thin film on FTO, ITO, and stainless steel by electrodeposition for electrochromic application

For electrochromic applications, binders are frequently employed to appropriately affix thin films to transparent conductive substrates like fluorine and indium-doped tin oxide glass plates (FTO and ITO) and stainless steel (SS). The different WO3 nanostructure materials are specifically formed using a variety of chemical and physical processes, but WO3 thin films are not sticky on the substrates without etching. Hence in the present research article, the nanostructured WO3 thin films were effectively deposited using straightforward, affordable anodic electrodeposition procedures on a variety of substrates, including ITO, FTO, and SS, without etching. The XRD analysis confirmed that the nanostructured WO3 materials exhibit amorphous nature (a-WO3). The uniformly deposited a-WO3 film shows the cracked morphological structures. The deposited a-WO3 film was confirmed by FTIR analysis. The nanostructured a-WO3 exhibits excellent electrochromic properties with the highest coloration efficiency (CE) on the FTO 191.4 cm2C-1 at 633 nm wavelength. The fastest electrochromic coloration (1.22 s) and bleaching (1.29 s) response time of nanostructured a-WO3 are observed on FTO substrates, respectively. The cycling stability of electrochromic a-WO3 was shown to be good up to 3000 cycles on FTO substrate.