Enhanced Photoluminescence and Optoelectronic Performance for Wrinkled 2D MoS₂ Through Strain Regulation

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Strain regulation for 2D molybdenum disulfide (MoS 2 ) has become an active topic. Here, the pre‐stretching method fabricates wrinkled 2D MoS 2 field‐effect transistors (FETs), which exhibit an ultra‐high on/off ratio (8.3 × 10 7 ). The impacts of wrinkles on enhanced photoluminescence (PL) and optoelectronic performance are systematically investigated by experiments and simulations. High‐resolution transmission electron microscopy (HRTEM) and Raman spectroscopy results indicate that the wrinkled 2D MoS 2 is subjected to a compressive strain (layer space decreases from 6.2 to 6.1 Å), alongside a redshift in the Raman signals. The PL intensity of wrinkled 2D MoS 2 shows a significant enhancement of up to 133% at the strain of 1.683%. Furthermore, the PL results suggest that the wrinkles can effectively adjust the bandgap (30 meV/%). The on/off ratio of the wrinkled FET is an order of magnitude higher than that of flat FET (2.0 × 10 6 ). Photoelectric measurements show that the dark and photocurrents of the wrinkled FET are enhanced by 200% and 47% at a gate voltage of 40 V, meanwhile, the response time is increased by 70%. Density‐functional theory (DFT) and technology computer‐aided design (TCAD) simulation are closely aligned with the experimental results for wrinkled 2D MoS 2 .