Structural, morphological, optical, and photocatalytic properties of Ag-doped MoS2 nanoparticles

Nanoparticles of Ag doped molybdenum disulfide (Ag-MoS2) were synthesized by hydrothermal process. The structural, morphological, and optical characterisics of these nanoparticles were characterized by scanning electron microscopy (SEM), Raman spectroscopy, and photoluminescence spectroscopy (PL), respectively. Raman spectra confirmed the formation of MoS2 and Ag-doped MoS2 nanoparticles. SEM images indicated that sheet-like structure is prepared in undoped MoS2, while Ag-MoS2 has a particlelike structure. PL peaks are observed at 600 nm (2.06 eV), 610 nm (2.03 eV), 700 nm (1.77 eV), 725 nm (1.71 eV), and 730 nm (1.69 eV) for pure, 1% and 2% Ag-MoS2. When the doping amount of Ag is increased further (i.e., to 3% Ag-doped MoS2), new peaks at 636 nm (1.9 eV) and 663 nm (1.87 eV) are observed due to an increase in structural defects. The photocatalytic activity (PCA) of undoped and Ag-MoS2 ( )is estimated by monitoring the degradation of rhodamine blue (RhB) and methylene blue (MB) dyes. The PCA of Ag-MoS2 samples are greater than that of undoped MoS2 when irradiated with visible light, which is attributed to increased electron-hole pair separation. (C) 2020 Elsevier B.V. All rights reserved.