Synergistic effect of MoS2 over WP photocatalyst for promoting hydrogen production

Via a simple hydrothermal method, the WP/MoS2 composites with the high hydrogen evolution activity were successfully synthesized. Moreover, the unique effect of MoS2 to the enhanced photocatalytic hydrogen production performance in the WP/MoS2 composites was systematically researched. The research shows that the WP/MoS2-1% composite has the best hydrogen evolution activity which reached 555.6 mu mol(-1) within 5 h, probably 3 times and 48 times higher compared to bare WP and MoS2, respectively. The inner reason of enhanced photocatalytic hydrogen evolution performance could be attributed to the followed aspects. Thin-film MoS2 coating on the surface of agglomerated WP nano-particles, not only reducing the electron transmission distance greatly but also significantly increasing the specific surface of the WP/MoS2-1% composite. Increased specific surface area tends to provide more active sites which is beneficial to the hydrogen evolution process. Furthermore, the established of type-II heterojunction between WP and MoS2 effectively suppressed the recombination rate of photo-induced electron-hole pairs and improved the separation and transfer rate of the electrons. All these factors together contribute to the enhanced photocatalytic hydrogen evolution performance by accelerating charge transfer rate, inhibiting the recombination of photo-induced electron-hole pairs and increasing active sites.