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

J Nanosci Nanotechnol. 2020 Feb 1;20(2):1118-1129. doi: 10.1166/jnn.2020.16968.

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.

Publication types

  • Research Support, Non-U.S. Gov't