전기변색 성능 향상을 위한 바나듐산화물 막의 결정성 제어 효과

In the present study, vanadium oxide(V₂O₅) films for electrochromic(EC) application are fabricated using sol-gel spin coating method. In order to optimize the EC performance of the V₂O₅ films, we adjust the amounts of polyvinylpyrrolidone(PVP) added to the solution at 0, 5, 10, and 15 wt%. Due to the effect of added PVP on the V₂O₅ films, the obtained films show increases of film thickness and crystallinity. Compared to other samples, optimum weight percent(10 wt%) of PVP led to superior EC performance with transmittance modulation(45.43 %), responding speeds(6.0 s at colored state and 6.2 s at bleached state), and coloration efficiency(29.8 cm²/C). This performance improvement can be mainly attributed to the enhanced electrical conductivity and electrochemical activity due to the increased crystallinity and thickness of the V₂O₅ films. Therefore, V₂O₅ films fabricated with optimized amount of PVP can be a promising EC material for high-performance EC devices.