Cost-effective Deposition of WO3 Films by AACVD method for Electrochromic applications: Influence of Precursor concentration

Abstract

In the present study, the effect of precursor concentration for WO₃ deposition by AACVD method was investigated. At the outset, H₂WO₄ was synthesized as the precursor for the deposition process. In the next step, H₂WO₄ solutions used in the AACVD process, with concentrations of 0.1, 0.5, and 1 M, were evaluated using a static wettability test. CV test revealed that at a concentration of 0.5 M, a higher number of charge carriers were involved in the redox process. CA and EIS tests were also employed to measure the impact of concentration on the electrochemical properties of the coated samples. Based on these findings, the concentration of 0.5 M was identified as optimal. Subsequently, Triton X-100 was added to the solution as a surfactant, and the deposition process was carried out. All the aforementioned tests were also conducted on the 0.5 M + Triton sample. Microstructural studies showed that the addition of Triton X-100 to the 0.5 M solution significantly improved the uniformity of the deposited tungsten oxide films. Based on optical measurements, the 0.5 M + Triton sample exhibited the optimal optical modulation (55.66%), and coloration efficiency (40.37 cm²C^-1) at the wavelength of 633 nm.