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

Abstract

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 × 10¹¹ and 2.7 × 10¹¹ Jones, respectively. This study lays critical technological groundwork for post-Moore optoelectronic integration chips and neuromorphic vision systems.