A non-volatile “programmable” transparent multilevel ultra-violet perovskite photodetector

Due to their outstanding physical properties, perovskite materials are considered to be promising semiconductors for next-generation optoelectronics. However, these materials are often unstable under an ambient atmosphere and ultra-violet illumination. Therefore, the construction of an air-stable visible light transparent perovskite-based ultra-violet photodetector is still highly challenging. In this study, we go beyond the conventional operation of photodetectors by utilizing the undesired hysteresis loop in the typical current-voltage characteristics of perovskites and design a (C4H9NH3)2PbBr4-based high-performance visible transparent programmable ultra-violet photodetector. The photodetector shows multiple operating levels and can switch from one level to another with a short electric pulse. The photodetector exhibits a fast response time of ∼2 ms, good responsivity of ∼32 mA W-1 and detectivity of 8.5 × 108 Jones with a low working voltage of 0.5 V. Moreover, the photodetector shows long-term stability, and the optoelectronic performance is retained under ambient conditions. This breakthrough in the controlled tunable features opens a new avenue for the development of multipurpose transparent optoelectronic devices.