Ultrabroadband, Ultraviolet to Terahertz, and High Sensitivity CH3NH3PbI3 Perovskite Photodetectors

Owning to the unique optical and electronic properties, organic-inorganic hybrid perovskites have made impressive progress in photodetection applications. However, achieving ultrabroadband detection over the ultraviolet (UV) to terahertz (THz) range remains a major challenge for perovskite photodetectors. Here, we report an ultrabroadband (UV-THz) dual-mechanism photodetector based on CH3NH3PbI3 films. The photoresponse of the PD in the UV-visible (vis) and near-infrared (NIR)-THz bands is mainly caused by the photoconductive (PC) effect and bolometric effect, respectively. High responsivities ranging from 105 to 102 mA W-1 are acquired within UV-THz bands under 1 V bias voltage at room temperature. Moreover, the device also shows fast rise and decay times of 76 and 126 ns under 1064 nm laser illumination, respectively. This work provides insight into the thermoelectric characteristics of perovskite and offers a new way to realize ultrabroadband photodetectors notably for THz detector at room temperature.