ReS 2 ‐Based Field‐Effect Transistors and Photodetectors

Atomically thin 2D layered transition metal dichalcogenides (TMDs) have been extensively studied in recent years because of their appealing electrical and optical properties. Here, the fabrication of ReS 2 field‐effect transistors is reported via the encapsulation of ReS 2 nanosheets in a high‐ κ Al 2 O 3 dielectric environment. Low‐temperature transport measurements allow to observe a direct metal‐to‐insulator transition originating from strong electron–electron interactions. Remarkably, the photodetectors based on ReS 2 exhibit gate‐tunable photoresponsivity up to 16.14 A W −1 and external quantum efficiency reaching 3168%, showing a competitive device performance to those reported in graphene, MoSe 2 , GaS, and GaSe‐based photodetectors. This study unambiguously distinguishes ReS 2 as a new candidate for future applications in electronics and optoelectronics.