Self-powered photodetectors based on CsPbBr3 quantum dots/organic semiconductors/SnO2 heterojunction for weak light detection基于CsPbBr3量子点/有机半导体/SnO2异质结的自供 电型探测器用于弱光检测

All-inorganic lead halide perovskite quantum dots (QDs) show great potential in the development of photodetectors (PDs) due to their excellent photoelectric properties. However, the photoresponse performance of the pure perovskite QDs-based PDs is usually limited by the poor charge transport efficiency of the perovskite QDs films. Here, high-performance self-powered PDs based on perovskite QDs and organic semiconductor PQT-12 (poly(3,3‴-didodecyl quarterthiophene)) are reported. Even in a self-powered mode, the devices can still show stable photoresponse to light signals and achieve excellent photodetection performance, including a detectivity up to 5.8 × 1012 Jones, and Ilight/Idark ratio up to 105. More importantly, the devices exhibit obvious photoresponse to weak light with intensity as low as 3 nW cm−2. To the best of our knowledge, the weak light detection ability of the device is better than most reported PDs based on perovskite QDs. In addition, the devices can be fabricated into flexible PDs with almost unchanged photocurrent under different bending angles. The overall performances of our devices are excellent among the reported self-powered PDs. This method utilized here provides new guides for developing high-performance self-powered PDs based on perovskite QDs for weak light detection.