Localized Exciton-Carrier Interactions at Laser-Defined Artificial Edges of MoS ₂ Probed by Temperature-Dependent Photoluminescence

We investigate the temperature-dependent photoluminescence (PL) characteristics of few-layer MoS2 with artificially engineered edges to unravel the interplay between excitonic and trionic emission processes. PL spectra recorded in the range 93–293 K reveal a distinct modulation of trion intensity relative to neutral excitons, with edge regions consistently exhibiting a more pronounced trion contribution than the basal plane. With increasing temperature, the emission peaks red-shift due to bandgap narrowing, arising from lattice expansion and electron–phonon interactions. To quantify this effect, we calculated the electron–phonon coupling constant for both edge and basal plane regions. Notably, edge regions display an enhanced coupling constant, comparable to that observed in monolayer MoS2 and significantly higher than that of the basal plane in few-layer samples. This enhancement highlights the role of artificially created edges as active sites that modify carrier localization, exciton–trion equilibrium, and phonon-mediated interactions.