Fabrication of Z-scheme magnetic MoS₂/CoFe₂O₄ nanocomposites with highly efficient photocatalytic activity

MoS₂ thin nanosheets decorated with CoFe₂O₄ nanoparticles have been successfully synthesized via a simple hydrothermal method. The nanocomposites are characterized by XRD, TEM, HRTEM, BET, XPS, UV-Vis DRS, PL and magnetic property analysis. The Z-scheme mechanism at the interface of MoS₂ and CoFe₂O₄ is formed. When the mass ratio of MoS₂ and CoFe₂O₄ is 1:3, the MoS₂/CoFe₂O₄ nanocomposites present excellent photocatalytic performance. The degradation rate of rhodamine B (RhB) and congo red (CR) is 93.80% and 94.43% in 90 and 50 min, respectively, under visible light irradiation. The highly photocatalytic activity could be mainly ascribed to the formed Z-scheme mechanism which facilitates the separation of photoinduced electron-hole pairs. Besides, the MoS₂ thin nanosheets not only provide the most active sites for photocatalytic reactions, but also act as the backing material for CoFe₂O₄ nanoparticles to effectively disperse and avoid the magnetic aggregation. Moreover, the MoS₂/CoFe₂O₄ nanocomposites present a good recyclability and the degradation rate of RhB and CR is still beyond 82% after seven runs. In addition, the nanocomposites can be easily separated by an external magnet.