Flexible UV photodetector based on copper tetraiodogallate (CuGaI4) film

The Cu-based halide semiconductor CuGaI₄ was prepared by a high-temperature melting method. Optoelectronic characterization and density functional theory calculations of CuGaI₄ reveal a direct bandgap of 2.9 eV. The corresponding UV photodetector (PD) based on CuGaI₄ demonstrates excellent UV response and rapid response time. In addition, a flexible PD based on CuGaI₄ is prepared, which also displays excellent photoresponse characteristics and mechanical stability. This work provides a systematic study of this novel Cu-based halide semiconductor and demonstrates the great potential of CuGaI₄ for future UV optoelectronic devices.