All-inorganic perovskite quantum dots (APQDs) have emerged as excellent materials which have been widely used in numerous micro-nano photoelectric devices. However, resistive random access memory (RRAM) devices based on APQDs are relatively scarce. In this work, RRAM based on CsPbBr3 APQDs prepared by the solution processed method was fabricated at room temperature. The sandwich structure memory device shows high reproducibility, good data retention ability, and light assisted multilevel storage capability. The resistance ratio (ON/OFF) of the RRAM device between the high resistance state and the low resistance state reaches almost 107. Additionally, the device exhibits high performances under low power consumption—low reading voltage (−0.3 V) and operation voltage (−2.4 V/1.55 V). It is suggested that the connection and rupture of conducting filaments, which are formed by Br vacancies under an electric field, are responsible for the resistive switching effect. Our work provides an opportunity to develop the next generation high-performance and stable nonvolatile memory devices.
Highly sensitive broadband photodetection is of critical importance for many applications. However, it is a great challenge to realize broadband photodetection by using a single device. Here we report photodetectors (PDs) based on three-dimensional (3D) graphene foam (GF) photodiodes with asymmetric electrodes, which show an ultra-broadband photoresponse from ultraviolet to microwave for wavelengths ranging from to . Moreover, the devices exhibit a high photoresponsivity of , short response time of 43 ms, and 3 dB bandwidth of 80 Hz. The high performance of the devices can be attributed to the photothermoelectric (PTE, also known as the Seebeck) effect in 3D GF photodiodes. The excellent optical, thermal, and electrical properties of 3D GFs offer a superior basis for the fabrication of PTE-based PDs. This work paves the way to realize ultra-broadband and high-sensitivity PDs operated at room temperature.