Photocatalytic hydrogen production by magnetically separable Fe3O4@ZnS and NiCo2O4@ZnS core-shell nanoparticles

Photocatalytic active material ZnS was grown on the surfaces of magnetic cores, Fe3O4 and NiCo2O4, by the solvothermal method to produce magnetically separable Fe3O4@ZnS and NiCo2O4@ZnS core-shell photocatalysts. These hydrogen production photocatalysts can be recycled by magnetic force for repeated hydrogen generation. The morphology, crystalline property, magnetic property, photocatalytic activity, and magnetic separation capability of the core-shell photocatalysts were studied. Fe3O4@ZnS based core-shell photocatalysts had better magnetic separation capability than the NiCo2O4@ZnS analog. The optimized photocatalytic hydrogen production rates of NiCo2O4@ZnS and Fe3O4@ZnS core-shell nanoparticles reached 880 μmol h−1 g−1 and 3900 μmol h−1 g−1, respectively. Both photocatalysts can be recycled by magnetic force. Recycled photocatalysts exhibited good hydrogen generation performance after being recycled for three times.