Characterization and electrochromic properties of CuxNi1−xO films prepared by sol–gel dip-coating

CuxNi1−xO electrochromic thin films were prepared by sol–gel dip coating and characterized by XRD, UV–vis absorption and electrochromic test. XRD results show that the structure of the Cux Ni1−xO thin films is still in cubic NiO structure. UV–vis absorption spectra show that the absorption edges of the CuxNi1−xO films can be tuned from 335 nm (x = 0) to 550 nm (x = 0.3), and the transmittance of the colored films decrease as the content of Cu increases. CuxNi1−xO films show good electrochromic behavior, both the coloring and bleaching time for a Cu0.2Ni0.8O film were less than 1 s, with a variation of transmittance up to 75% at the wavelength of 632.8 nm.