Hydrothermal synthesis of MoS₂ nanosheet loaded TiO₂ nanoarrays for enhanced visible light photocatalytic applications

Abstract

A molybdenum disulfide (MoS₂) nanosheet-decorated titanium dioxide (TiO₂) NRA heterojunction composite was fabricated successfully through a two-step hydrothermal approach. Microstructures and optical properties of specimens were characterized by field-emission scanning electron microscopy, X-ray diffractometry, X-ray photoelectron spectroscopy, and ultraviolet-visible spectroscopy. The gaps of the TiO₂ nanorods have been filled with tiny MoS₂ nanosheets, which can increase the surface area of MoS₂/TiO₂ NRA composite thin films. In addition, the photocatalytic activity of the thin films were measured and discussed in greater detail. The appropriate hydrothermal reaction temperature of MoS₂ is important for the growth of perfect MoS₂/TiO₂ NRA composites with significantly enhanced photocatalytic performance. The photodegradation rate and <i>k</i> value of MoS₂-220/TiO₂ are 86% and 0.0105 min^-1, respectively, which are much larger than those of blank TiO₂. The enhanced photocatalytic performance could be attributed to the higher visible light absorption and the reduced recombination rate of photogenerated electron-hole pairs.