Van der Waals integrated plasmonic Au array for self-powered MoS₂ photodetector

2D transition metal dichalcogenides such as MoS₂ are promising candidates for optoelectronics because of atomically thin nature and strong light–matter interaction. However, the poor light absorption limited their photodetection performance. Surface plasma resonance (SPR) can improve light absorption, but the defects introduced during the metal deposition process limit their responsivity and response time. In this work, we transfer a plasmonic Au array onto MoS₂ surface, in which van der Waals (vdWs) contact forms between defect-free Au array–MoS₂ interface. The Au/MoS₂ heterostructure photodetector performs 1.8 ms rising time, 186.6 A/W responsivity, and 1.41 × 10¹² Jones detectivity. The damage free vdWs fabrication method also makes it possible to integrate the engineered SPR Au array with functional polymer for flexible electronics. Thus, a vdWs plasmonic Au array/MoS₂/P(VDF-TrFE) photodetector with a 1.28 × 10³ rectification ratio has been obtained. This approach not only optimizes the performance of the 2D optoelectronic devices but also expands the scope of its potential applications.