Synergistic Enhancement of Photoresponse and Broadband Detection via Quantum Dot-Sensitized Hexagonal Nanoporous MoS₂ matrix

Advanced semiconducting materials such as transition metal dichalcogenides exhibit significant potential for the development of next-generation optoelectronic devices. Specifically, the construction of an efficient heterostructure is imperative for achieving enhanced sensing capabilities, particularly in broadband light detection. In this study, a novel adaptive approach to enhance the photosensing abilities of multilayer MoS₂ is introduced, as it is more easily fabricable compared to its single-layer counterparts. Here, devices based on a mixed-dimensional van der Waals heterostructure utilizing CdSe/ZnS core–shell quantum dots and hexagonal nanoporous MoS₂ are proposed. Bandgap engineering is introduced by deliberately created nanoporous structure in MoS₂. The generated sub-gap states enable a unique photophysical interaction when integrated with quantum dots. This quantum dot sensitized effect, observed both optically and electrically, extends the optical detection range into the near-infrared region (up to 1100 nm). These phototransistors exhibit high photoresponsivity values, reaching up to 2.55 × 10⁴ A W⁻¹ at V_gs = 30V. The results highlight the connection between the quantum dot sensitized mechanism and the electrical realization of broadband detection in practical devices. The proposed devices have substantial potential, explicating their technological relevance as a cutting-edge, high-performance, and broadband photodetector, well-suited for developments in optoelectronic applications.