Simulation and experimental studies of FTO/WO₃ and FTO/WO₃/Ag thin film structures for electrochromic analysis deposited by DC & RF magnetron sputtering

In this work, DC & RF magnetron sputtering and COMSOL multiphysics were used to simulate and deposit WO₃ and WO₃/Ag films, respectively. In the simulation cyclic voltammetry (CV) analysis was examined. The current density for the WO₃/Ag films in comparison to the WO₃ film was displayed higher. Based on the simulation findings, the experiment was done using DC & RF magnetron sputtering to deposit WO₃ and WO₃/Ag films. Scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–vis spectrometer, and electrochemical analyzer were used to examine the structural, morphological, EC, and optical characteristics of the deposited films. The SEM study revealed a smooth surface for WO₃ films and WO₃/Ag shows the grain of silver film. The XRD analysis of WO₃ films shows the amorphous nature and in WO₃/Ag films silver peaks were shown. The bandgap value_s were found to be 3.14 eV and 3.02 eV for WO₃ and WO₃/Ag films, respectively. Comparing the WO₃/Ag film to the WO₃ film, the cyclic voltammograms showed that the WO₃/Ag film had the maximum current. In comparison to the WO₃ film (30 cm²C⁻¹), higher coloring efficiency values were noted for the WO₃/Ag film (48 cm²C⁻¹). For the WO_3/Ag film, less time is needed for the coloring (tc = 2.2) and belching (tb = 1.8 s). It was clear that compared to a single-component WO₃ film, the Ag-embedded WO₃ composite system performed noticeably better electroactively and electrochemically.