A Novel MoS2/TiO2/Graphene Nanohybrid for Enhanced Photocatalytic Hydrogen Evolution under Visible Light Irradiation

Graphene is regarded as a potential co-photocatalyst for photocatalytic hydrogen (H2) evolution, but its great photocatalytic ability requires tuning the band gap structure or design morphology of composites. In this study, MoS2/TiO2/graphene (MTG) nanohybrids were fabricated at varied ratios of graphene and served as co-photocatalysts for H2 evolution. The results exhibited that the H2 evolution of MTG-10 obtained is much better than others. The amount of hydrogen evolution was high, which was found to be 4122 μmol g−1 of H2 in 5 h with photocatalytic systems, which is almost 7.5~13.4 times greater than that of previous pristine MoS2 (548 μmol g−1) and TiO2 (307 μmol g−1) samples, respectively. This is significantly attributed to the graphene as a bridge of MoS2/TiO2 and the incorporation of graphene, suggesting the synergistic effect of the rapid electron-transferring of photoinduced electrons and holes and the powerful electron-collecting of graphene, suppressing the charge recombination rate.