The structure and electrochromic properties of vanadium pentoxide nanocomposite films supported within ZnO nanorod array

V 2 O 5 has attracted extensive research interest in the field due to its unique capability of both anodic and cathodic electrochromism. In this study, ZnO/V 2 O 5 nanocomposite films were fabricated by incorporating ZnO nanorod arrays into V 2 O 5 films via a combination of electrochemical deposition and spin‑coating. The electrochemical and optical properties of the composite films were characterized by cyclic voltammetry, chronoamperometry, UV‑Vis spectroscopy, and colorimetric analysis. The results show that the ZnO/V 2 O 5 composite films exhibits fast electrochromic switching (t c /t b = 2 s/2.6 s) and can reversibly switch among blue‑gray, olive‑green, yellow‑green, and yellow colors. It also achieves a high transmittance modulation of 31.33% at 550 nm, a wavelength to which the human eye is highly sensitive. This work proposes a new strategy for the preparation of ZnO/V 2 O 5 composite films, and this strategy offers new insights into obtaining fast-response electrochromic films.