Infrared Phototransistor Induced by MoS2 Quantum Dots Encapsulated in Lead Iodide Perovskite

A reliable, highly efficient phototransistor would enable multifunctional photodetection and amplification and would also allow for electrical signal-readout processes. Lead halide perovskite semiconductors are known to generally have large mobilities and carrier lifetimes, which make them ideal candidates as photodetectors and for use in other electronics. Here, we demonstrate an infrared perovskite/MoS
₂
quantum dots' (QDs) phototransistor with a quick detection speed (40 μs), high detectivity (5 × 1011 Jones) even at high frequencies (104 Hz), reasonable linearity, and a wide spectrum response in infrared wavelengths. The realization of efficient infrared detection is due to the effective photo-induced charge between the perovskite/QDs' interface, which is achieved by combining the modulation of the electrical gate and optical light. These results are advantageous for infrared perovskite phototransistors.