Manipulating Carrier Behavior by the Size Effect of Decoration in MoS2 Photodetectors

Abstract

As an eye-catching 2D material, MoS₂ has tunable optical and electrical properties. However, the rapid recombination of electron-hole pairs intrinsically significantly hinders the performance improvement of MoS₂ photodetectors. Achieving carrier manipulation to suppress recombination is crucial and challenging for MoS₂ photodetectors. Herein, we report three MoS₂ photodetectors decorated with platinum single atoms (Pt SAs), platinum single-layer clusters (Pt SCs), and platinum nanoclusters (Pt NCs) via an impregnation method. Carrier recombination in MoS₂ is suppressed by growing Pt SAs, Pt SCs, and Pt NCs. Furthermore, Pt SAs, Pt SCs, and Pt NCs have different effects on carrier behavior due to the size effect and disparate interactions with MoS₂. Among the Pt SA/MoS₂, Pt SC/MoS₂, and Pt NC/MoS₂ devices, Pt SC/MoS₂ exhibits a responsivity (R) of 1.44 × 10² A W⁻¹ and a specific detectivity (D*) of 1.07 × 10¹⁰ Jones under 532 nm illumination with a power density of 0.5 mW cm⁻². This work will deepen the understanding of the relationship between the size effect and carrier behavior and provide a theoretical basis for carrier manipulation of photodetectors.