Unveiling thermally driven photoluminescence in CVD grown MoS2 dendritic flake

High-quality MoS${}_2$ nanostructures were fabricated via chemical vapor deposition technique on SiO₂/Si substrate. In this paper, the effect of temperature on the photoluminescence behavior of MoS${}_2$ dendritic flake is addressed. We scrutinized the photoluminescence spectra of monolayer and multilayer regions of MoS${}_2$ in the temperature range 300 K–680 K. Monolayer and multilayer behavior of MoS${}_2$ flakes are confirmed by Raman and Photoluminescence spectroscopy. The excitonic peaks from the multilayer regime become less intense and show a red shift compared to the monolayer PL spectra. Thermally-induced bandgap modulation of MoS${}_2$ is demonstrated. The excitonic intensity and peak positions reveal pronounced temperature-dependent changes. These changes are explicable through the increased electron–phonon interaction and lattice rearrangements. Furthermore, first principle calculations are employed to glean insight into the impact of atomic rearrangements on the band gap behavior of MoS${}_2$. Our research presents a detailed understanding of thermally driven band gap modulation of monolayer and multilayer MoS${}_2$, which is essential for designing optoelectronic devices.