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Self-driven photodetectors are widely used in communication and imaging. As a newly developed semiconductor material, perovskite quantum dots (QDs) are not only bandgap tunable, but also easily combined with other materials. In this paper, a vertical structure self-driven photodetector based on heterojunction of CsPbBr3 QDs and PbS QDs is proposed, and the device is prepared by solution spin coating method. The device can work in visible and near infrared (400–1130 nm) regions, and has excellent performance, such as ultrafast response speed (rise and decay time are 0.4 μs/0.73 μs under 532 nm laser irradiation in self-driven mode, the estimated response time under 1064 nm laser irradiation is about 11.5 μs), more than 100 dB linear dynamic range for both visible and infrared regions, and good stability. Similarly, the responsivity of the photodetector can also reach an average of 10 mA W−1, and the detectivity is 1.13 × 1010 Jones at 0 V bias for 1064 nm laser irradiation. The device combines two kinds of QDs revealing its good prospects and great advantages in self-driven photodetectors and high-speed optical communication devices. [ABSTRACT FROM AUTHOR]

Light enhanced low-voltage nonvolatile memory was prepared using all-inorganic perovskite quantum dots (QDs) as a semiconductor layer and Ag nanoparticles (NPs) as a floating gate layer. The photo-induced carriers can be produced in CsPbBr3 QDs under ultraviolet light and trapped in Ag NPs under the action of an external electric field. With the assistance of light, the device exhibited a significantly larger memory window (ΔVth) under low programming and erasing voltages of ±5 V owing to the use of CsPbBr3 QDs. Furthermore, we proved that the ΔVth of the memory strongly depended on the applied bias voltage (VDS) as well as still remaining at 79.3% after 105 s at VDS of 1.4 V. The facile memory provides a new approach to trap a photo-induced charge and reduce operating voltages by combining QDs with metal NPs. [ABSTRACT FROM AUTHOR]