Manipulating Carrier Behavior by the Size Effect of Decoration in MoS ₂ Photodetectors

Abstract As an eye‐catching 2D material, MoS ₂ has tunable optical and electrical properties. However, the rapid recombination of electron‐hole pairs intrinsically significantly hinders the performance improvement of MoS ₂ photodetectors. Achieving carrier manipulation to suppress recombination is crucial and challenging for MoS ₂ photodetectors. Herein, we report three MoS ₂ 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 MoS ₂ 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 MoS ₂ . Among the Pt SA/MoS ₂ , Pt SC/MoS ₂ , and Pt NC/MoS ₂ devices, Pt SC/MoS ₂ exhibits a responsivity (R) of 1.44 × 10 ² A W ⁻¹ and a specific detectivity (D*) of 1.07 × 10 ¹⁰ 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.