Hydrothermal Synthesis of Mn_3O_4/CoS_2 as a Promising Photocatalytic Material for Boosting Visible-Light Photocatalytic Hydrogen Production

摘要

Photocatalytic hydrogen evolution has received extensive attention for energyconversion and storage of clean energy. Herein, the composite catalyst Mn_3O_4/CoS_2 is successfully prepared by a hydrothermal method. Photocatalytichydrogen evolution experiments are conducted by adjusting the amount ofMn_3O_4. The results show that the composite photocatalyst Mn_3O_4/CoS_2 hashigher photocatalytic hydrogen evolution performance. The hydrogen productionof the 50 mg Mn_3O_4/CoS_2 composite catalyst at 5 h is 14.95 times and 1.60 timesthat of pure Mn_3O_4 and CoS_2, respectively, indicating that the 50mg Mn_3O_4/CoS_2 composite catalyst has good photocatalytic stability. In addition, thestructure, morphology, and composition of the prepared catalysts are characterizedby scanning electron microcopy (SEM), transmission electron microscopy(TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS),Brunauer–Emmett–Teller (BET), electrochemical and PL techniques. Comparedwith Mn_3O_4 and CoS_2, the photocatalytic response of the 50 mg Mn_3O_4/CoS_2composite catalyst is significantly enhanced, the current density is increased, thefluorescence quenching efficiency is accelerated, and the pore volume and poresize are increased. Therefore, the composite catalyst can accelerate the separationand transfer of photogenerated electrons and holes and improve thephotocatalytic efficiency.