石墨烯-ZnIn_2S_4纳米复合微球的制备及光催化产氢活性

Preparation and Photocatalytic Activity for Hydrogen Evolution of Graphene-ZnIn_2S_4 Nanocomposite Spheres

采用光催化还原法制备了石墨烯-Zn In2S4纳米复合微球。采用XRD、SEM、TEM、FT-IR、XPS和DRS等手段对样品进行表征,结果表明,经过光催化还原处理后氧化石墨被还原成石墨烯,Zn In2S4纳米微球负载在石墨烯表面。光催化产氢的实验结果表明,当石墨烯含量为2.0wt%、光催化还原时间为24 h时,石墨烯-Zn In2S4纳米复合微球在模拟太阳光下产氢量达到1540.8μmol,是纯Zn In2S4纳米微球的9.8倍。增强光催化性能的原因归结为石墨烯在复合光催化剂中起到了电子快速传输作用,同时还对纳米复合微球光催化产氢反应机理进行了分析讨论。

Graphene-ZnIn2S4 nanocomposite spheres were prepared via a facile photocatalytic reduction method. The samples were characterized by XRD, SEM, TEM, FT-IR, XPS and DRS. The results showed that the graphene oxide was reduced to graphene and ZnIn2S4 nanospheres were loaded on the surface of graphene sheets through a photocatalytic reduction process. The experimental results for photocatalytic hydrogen evo-lution of the samples indicated that the amount of evoluted H2 under simulated sunlight irradiation using gra-phene-ZnIn2S4 nanocomposite spheres was 1540.8μmol, 9.8 times of the pure ZnIn2S4 nanospheres, under op-timal technological condition with the graphene content of 2.0wt% for 24 h. The enhanced performance can be attributed to the graphene which effectively promoted the transfer of photogenerated electrons. Furthermore, a detailed photocatalytic hydrogen evolution mechanism of graphene-ZnIn2S4 nanocomposite spheres was in-vestigated.