High-performance flexible and broadband photodetectors based on PbS quantum dots/ZnO nanoparticles heterostructure

Flexible and broadband photodetectors have drawn extensive attention due to their potential application in foldable displays, optical communications, environmental monitoring, etc. In this work, a flexible photodetector based on the crystalline PbS quantum dots (QDs)/ZnO nanoparticles (NPs) heterostructure was proposed. The photodetector exhibits a broadband response from ultraviolet-visible (UV-Vis) to near infrared detector (NIR) range with a remarkable current on/off ratio of 7.08×103 under 375 nm light illumination. Compared with pure ZnO NPs, the heterostructure photodetector shows the three orders of magnitude higher responsivity in Vis and NIR range, and maintains its performance in the UV range simultaneously. The photodetector demonstrates a high responsivity and detectivity of 4.54 A W−1 and 3.98×1012 Jones. In addition, the flexible photodetectors exhibit excellent durability and stability even after hundreds of times bending. This work paves a promising way for constructing next-generation high-performance flexible and broadband optoelectronic devices.