Disintegration of Flower-Like MoS2 to Limply Allied Layers on Spherical Nanoporous TiO2: Enhanced Visible-Light Photocatalytic Degradation of Methylene Blue

Abstract

MoS2/TiO2 heterostructure with enhanced photocatalytic activity was successfully synthesized by hydrothermal method. The segmentation of flower-like MoS2 structure resulted, during the hydrothermal condition in the presence of spherical nanoporous TiO2 as a growing matrix. A pool of larger spherical TiO2 particle induces a strain effect, which restricted the size of MoS2. Meanwhile, the applied hydrothermal pressure leads the segmentation of the bundle-like structure of MoS2 to individual layer. The obtained heterostructure was characterized by X-ray diffraction, Scanning, and Transmission electron microscopy, X-ray photoelectron spectroscopy, DRS-UV Visible spectra, Photoluminescence, Raman spectroscopy and BET surface area analysis. The photocatalytic activity of these synthesized materials was evaluated for the decomposition of methylene blue (MB) under visible light. The results indicated that MoS2/TiO2 heterostructure had higher photocatalytic activity than pristine MoS2 and TiO2 materials. After irradiation, the photocatalytic efficiency towards MB degradation was calculated as 67.4, 80.2 and 99.5% for MoS2, TiO2, and MoS2/TiO2, respectively. The formation of unique, distinct layers of MoS2 over TiO2 surface created more active sites for a photocatalytic response. These whole phenomena could enhance the absorption characteristics of dyestuff on the heterostructure and enhance the charge transport after conjugation, which improves MB degradation efficiency.