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.