Facile synthesis of C–TiO2–MoS2 nanocomposite based on commercial TiO2 nanopowder for photodegradation of methylene blue

Abstract

We present a facile synthesis method for a C–TiO₂–MoS₂-based photocatalytic nanocomposite designed for the efficient degradation of pollutant dyes, specifically methylene blue (MB) and rhodamine B (RhB). Few-layered MoS₂ nanosheets were exfoliated from natural bulk MoS₂ via urea-assisted ball milling. These nanosheets were then mixed with TiO₂ nanopowder and sodium deoxycholate (SDC) surfactant, followed by thermal annealing at 600 °C in argon (Ar) gas. The resulting TiO₂–MoS₂ mixture was found to be coated and interconnected by a carbon layer, which acted as an electron-conducting bridge and simultaneously prevented the aggregation of TiO₂ nanoparticles and MoS₂ nanosheets. The photocatalytic performance of the nanocomposite was evaluated through the degradation of MB and RhB. Remarkably, the nanocomposite exhibited excellent degradation of a high-concentration MB (RhB) solution (10⁻⁴ M), achieving near-complete degradation within 45 minutes under UV light and 50 minutes under visible light. Furthermore, under UV irradiation, the nanocomposite reached a degradation efficiency of 99.6% with a rate constant of 0.128 min⁻¹, while slightly lower values were observed under visible light. A possible mechanism responsible for the enhanced MB degradation was also proposed. This strategy provides a promising pathway for the development of effective photocatalysts for practical photocatalytic applications.