Electrochromism is widely used in the field of smart windows, but electrochromic materials still require external power to support them. The combination of solar cells and electrochromic materials can achieve intelligent color control without external power supply. The excellent performance of color changing cathodes and photoanodes are currently a research hot topic in photoelectrochromic devices.WO₃-MoO₃ thin films were prepared by hydrothermal method and their electrochromic performances were studied; TiO₂/CdS composite thin films were prepared by hydrothermal method combined with continuous ion layer deposition method, and their photoelectric conversion performances were studied. Finally, WO₃-MoO₃ thin film and TiO₂/CdS composite thin film were used as the color changing cathodes and photoanodes of the photoelectrochromic devices, respectively. WO₃/MoO₃-TiO₂/CdS photoelectrochromic devices. WO₃/MoO₃-TiO₂/CdS photoelectrochromic devices have a large optical modulation range (41.99% at 630nm) and higher coloration efficiency (35.787%), making them of great application value as smart windows in modern buildings, transportation tools, and other fields.