A novel MoS₂/ tourmaline /graphene ternary composite with enhanced visible-light photocatalytic property

Abstract

In this study, MoS2-graphene-tourmaline (MoS2-GR-T) composite photocatalyst was successful synthesized via one-step hydrothermal method. Raman spectra revealed that graphene oxide was reduced to graphene. Scanning electron microscopy images showed that MoS2 was dispersed well on graphene. Transmission electron microscope images showed that MoS2 and tourmaline contacted well with graphene. Analysis of UV-visible diffuse reflectance spectra implied that the bandgap energies of MoS2, MoS2-T and MoS2-GR-T samples were 2.01 eV, 1.91 eV and 1.79 eV, respectively. The photocatalytic performances are evidenced under Xenon lamp irradiation utilizing Rhodamine B dye as the model compound. Compared with MoS2 and MoS2-GR, the MoS2-graphene-tourmaline (MoS2-GR-T) composites exhibited the excellent photocatalytic activity for the degradation about irradiating for 60 min were 93.9% under visible-light. The enhanced photocatalytic activity of MoS2-GR-T composite could be attributed to the exposed adsorption-photocatalytic active sties, the improved light adsorption ability and the promoted charge separation efficiency. The introduction of tourmaline reduced the band gap explored by analysis of UV-visible diffuse reflectance spectra. This work demonstrated that the charge efficiency of photocatalysts could be promoted by coupling both metal-free co-catalyst and polar mineral.