NiSe2 nanoparticles modified ZnIn2S4 microspheres for boosting photocatalytic hydrogen evolution under visible light irradiation

A well-designed composite based on semiconductor materials can effectively reduce the recombination of photogenerated carriers in photocatalysts by establishing efficient charge transfer channels, which enhances the activity of photocatalytic hydrogen evolution for water splitting. Herein, a ZnIn2S4/NiSe2 composite with NiSe2 nanoparticles tightly anchored on the nanosheets-assembled microspheres ZnIn2S4 was elaborated and successfully synthesized by a hot-injection method followed by a successive solvothermal method. The synergistic effects and close contact interface between ZnIn2S4 and NiSe2 facilitated charge migration. Under visible light irradiation, the optimal ratio of ZnIn2S4/NiSe2 composite achieved an outstanding hydrogen evolution rate of 3060 mu mol g-1 h-1 (nearly 12.6 times of unmodified ZnIn2S4) and exhibited superior stability (no apparent decrease within 20 h) in the presence of a sacrificial agent (triethanolamine). Additionally, various characterizations revealed that the recombination of photo-generated carriers was effectively suppressed, visible-light absorption was significantly enhanced, and interface charge transfer was accelerated, thus endowing the ZnIn2S4/NiSe2 composite with superior photocatalytic activity. This research provides illuminating insights into using the non-noble metal-based catalyst NiSe2 as an effective co-catalyst, significantly improving photocatalytic performance and holding great potential in alleviating energy shortages and environmental pollution problems.