Utilization of a ZnS(en)_0.5 photocatalyst hybridized with a CdS component for solar energy conversion to hydrogen

Photocatalytic solar energy conversion to chemical energy attracts great attention due to its high potential in harvesting renewable energy for the future. A ZnS(en)_0.5 photocatalyst hybridized with a CdS component was synthesized by solvothermal and precipitation methods to compare the effect of preparation methods on photocatalytic performance. The highest hydrogen production rate (559 μmol g⁻¹ h⁻¹) was achieved from a solvothermally synthesized ZnS(en)_0.5−CdS composite at 80 wt% of CdS content under standard 1-sun-irradiation condition (1000 W/m²). Photocatalytic hydrogen production rates from ZnS(en)_0.5−CdS photocatalysts were highly associated with degrees of charge separation, crystallinity, reduction power, and light absorption. By comparing two different routes for the synthesis of ZnS(en)_0.5−CdS photocatalysts, solvothermally-fabricated material was shown to have a higher photocatalytic activity compared with material fabricated by a precipitation method. This improvement may be due to its excellent crystalline and charge-separation characteristics.