High-performance optoelectronics enabled by synergistic integration of 2D heterostructures with perovskite quantum dots

In the era of IoE- and AI-driven intelligent optoelectronics, ultrafast, highly sensitive photoelectric systems are crucial for quantum information, autonomous driving, and biosensing. To overcome the limitations of long photo-response/recovery times in single-material devices and restricted photo-response times in heterojunctions, high-performance 2D electronic heterostructure devices with enhanced photocurrents and rapid response rates through quantum dots (QDs) surface modification were fabricated in this study. First, CsPbBr3 QDs were decorated on the surfaces of MoS2, WS2 and BP. Raman spectroscopy and Kelvin probe force microscopy (KPFM) analyses conclusively demonstrate the n-type doping characteristics induced by QDs integration, whereas photoluminescence (PL) spectroscopy combined with fluorescence lifetime measurements systematically further reveals nanosecond interfacial charge transfer dynamics at the heterojunction. Based on such highly efficient interface carrier transfer processes, we fabricated heterostructure devices based on CsPbBr3/WS2/MoS2 and CsPbBr3/BP/MoS2 and evaluated their photoelectric performances. Decoration of CsPbBr3 QDs effectively enhances the photocurrents of the original heterostructure devices, as well as shortens their response/recovery times and responsivities. Notably, CsPbBr3/WS2/MoS2 exhibits a higher photoelectric enhancement performance, whereas CsPbBr3/BP/MoS2 is capable of maintaining lower dark currents. Beyond experiments, density functional theory (DFT) was also used to corroborate the efficient photocurrent generation mechanism of the above device structures. Under 600 nm illumination, the CsPbBr3/WS2/MoS2 and CsPbBr3/BP/MoS2 heterostructures achieved exceptional responsivity (R) of 248 A W-1 and 220 A W-1 with detectivity (D*) of 1.3 x 1011 and 2.7 x 1011 Jones, respectively. This study lays critical technological groundwork for post-Moore optoelectronic integration chips and neuromorphic vision systems.