High-sensitivity hybrid MoSe2/AgInGaS quantum dot heterojunction photodetector

Abstract

Zero-dimensional (0D)–two-dimensional (2D) hybrid photodetectors have received widespread attention due to their outstanding photoelectric performances. However, these devices with high performances mainly employ quantum dots that contain toxic elements as sensitizing layers, which restricts their practical applications. In this work, we used eco-friendly AgInGaS quantum dots (AIGS-QDs) as a highly light-absorbing layer and molybdenum diselenide (MoSe₂) as a charge transfer layer to construct a 0D–2D hybrid photodetector. Notably, we observed that MoSe₂ strongly quenches the photoluminescence (PL) of AIGS-QDs and decreases the decay time of PL in the MoSe₂/AIGS-QDs heterojunction. The MoSe₂/AIGS-QDs hybrid photodetector demonstrates a responsivity of 14.3 A W⁻¹ and a high detectivity of 6.4 × 10¹¹ Jones. Moreover, the detectivity of the hybrid phototransistor is significantly enhanced by more than three times compared with that of the MoSe₂ photodetector. Our work suggests that 0D–2D hybrid photodetectors with multiplex I-III-VI QDs provide promising potential for future high-sensitivity photodetectors.