Heteroepitaxial Strain Engineering and Interfacial Energy Transfer Boosting Optoelectronic Properties in C ₆₀ /WS ₂ van der Waals Heterostructures

Abstract

Abstract Engineered van der Waals (vdW) heterostructures, combining molecular semiconductors and atomically flat nanomaterials, offer vast opportunities to tailor optoelectronic properties at heterointerfaces. Here, the heteroepitaxial assembly of C 60 molecules on monolayer tungsten disulfide (ML‐WS 2 ), where an anisotropic compression strain within the C 60 lattice at the heterointerface induces the formation of 1D polymeric C 60 strings and activates otherwise symmetry‐forbidden S 1 → S 0 optical transitions, is reported. This, coupled with interfacial energy transfer from ML‐WS 2 to C 60 , results in a remarkable 310% enhancement in the PL intensity compared to disordered C 60 aggregates. The resulting C 60 /ML‐WS 2 transistors exhibit superior electrical and optoelectronic performance, achieving a charge carrier mobility of 10.4 cm 2 V −1 s −1 , facilitated by an ultralow 230 meV contact barrier with Au electrodes. These devices demonstrate a superior photoresponsivity of 46.4 A W −1 and a detectivity of 3.6 × 10 12 Jones, greatly outperforming pristine ML‐WS 2 counterpart devices.