Tailoring band gap, structural, and optical properties of CVD-grown few-layer MoS2 via swift heavy-ion irradiation

Two-dimensional (2D) transition metal dichalcogenides (TMDs) are of great interest for next-generation electronic and optoelectronic devices due to their unique band structures. Here, we report the synthesis of high-quality few-layer MoS 2 films using the sodium chloride (NaCl)-assisted chemical vapor deposition (CVD) method. This approach enables growth at a reduced temperature of 650֯C, significantly lower than the conventional 850֯C. Structural and morphological characterizations performed using optical microscopy, SEM, TEM, synchrotron-based XRD, Raman spectroscopy, UV–Vis spectroscopy, and Rutherford backscattering spectrometry (RBS) confirm crystalline, uniform, and nearly defect-free films. The Raman A 1g -E 2g 1 mode separation of ≈24.5 cm -1 and RBS measurements indicate