ZnFe2O4 decorated CdS nanorods as a highly efficient, visible light responsive, photochemically stable, magnetically recyclable photocatalyst for hydrogen generation

Abstract

Charge separation, protection of photocatalysts from hole attacks, and easy recyclability, which are of paramount importance in the development and applications of highly efficient and photochemically stable nanosized semiconductor photocatalysts, were achieved simultaneously by paramagnetic ZnFe₂O₄ nanocrystal decorated CdS nanorods. The photo-induced holes of CdS tend to migrate to the photochemically stable ZnFe₂O₄ domain while the photo-induced electrons of ZnFe₂O₄ tend to migrate to the photochemically more active CdS domain, achieving CdS protection and electron–hole separation. Decoration of ZnFe₂O₄ nanocrystals on CdS nanorod surfaces was achieved with a solvothermal process, giving a highly efficient, visible light responsive, photochemically stable, magnetically recyclable photocatalyst for hydrogen generation through water splitting. Specific hydrogen evolution rates as high as 2.44 mmol g⁻¹ h⁻¹ were achieved with the present product under visible light illumination, with its long term stability demonstrated.