摘要
Heterojunction is regarded as a crucial step toward realizing high-performance devices,particularly,forming gradient energy band between heterojunctions benefits self-powered photodetectors.Therefore,in this paper,the synthesis of CsPbI3 nanorods(NRs)and its application as the interfacial layer in high-performance,all-solution-processed self-powered photodetectors are presented.For the bilayer photodetector ITO/ZnO(100 nm)/PbS-TBAI(150 nm)/Au,a responsivity of 3.6 A/W with a specific detectivity of 9.8×10^(12)Jones was obtained under 0.1 mW/cm^(2)white light illumination at zero bias(i.e.in self-powered mode).Meanwhile,the photocurrent was enhanced to an On/Off current ratio of 105 at zero bias with an open circuit voltage of 0.53 V for trilayer photodetector ITO/ZnO(100 nm)/PbSTBAI(150 nm)/CsPbI3(250 nm)/Au,in which the CsPbI3 NRs layer works as the interfacial layer.As a result,a specific detectivity of 4.5×10^(13)Jones with a responsivity of 11.12 A/W was obtained under0.1 mW/cm^(2) white light illumination,as well as the rising/decaying time of 0.57 s/0.41 s with excellent stability and reproducibility upto four weeks in air.The enhanced-performance is ascribed to the mismatch bandgap between PbS-TBAI/CsPbI_(3)interface,which can suppress the carrier recombination and provide efficient transport passages for charge carriers.Thus,it provides a feasible and efficient method for high-performance photodetectors.
基金
partially funded by the project of State Key Laboratory of Transducer Technology(SKT1404)
the project of the Key Laboratory of Photoelectronic Imaging Technology and System(2017OEIOF02)Beijing Institute of Technology,Ministry of Education of China
the project of the Key R&D projects of the Ministry of Science and Technology(SQ2019YFB220038)。