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论文类型：期刊论文

发表时间：2019-06-01

发表刊物：JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY

收录刊物：SCIE、PubMed

卷号：19

期号：6

页面范围：3519-3527

ISSN号：1533-4880

关键字：MoS2; Visible Light; Photocatalytic

摘要：Molybdenum disulfide (MoS2), as a typical layered transition metal sulfide, has been widely used in photocatalysis. Here, we report layered MoS2 nanosheet-coated TiO2 heterostructures that were prepared using a simple photo-assisted deposition method. The as-prepared samples were investigated in detail by using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. Results demonstrated that the MoS2 nanosheets uniformly covered the outer surface of TiO2. The visible light-sensitive photocatalytic activity was evaluated by the removal of methylene blue (MB) and 2-chlorophenol (2-CP) in aqueous solution. Thus, the MoS2/TiO2 heterostructures exhibited improved photocatalytic degradation activity under visible light compared with the pure TiO2. Under visible light irradiation for 90 min, the degradation efficiencies of MB and 2-CP over the MoS2/TiO2 sample (sunlight irradiation time: 30 min) are as high as 93.6% and 70.6%, respectively. Furthermore, the corresponding mechanism of enhanced photocatalytic activity is proposed on the basis of the comprehensively investigated results from the radical trapping experiments, photoluminescence spectroscopy, and electron spin resonance analysis. The hole oxidation, hydroxyl radicals, and superoxide anion radicals act as the active species simultaneously in the photodegradation of the dye molecules. However, of these species, hole oxidation played the most important roles in the photocatalytic reaction.