Cu doped ZnFe2O4 photocatalysts for enhanced hydrogen production and dye degradation in the visible region

Abstract

Cu doped ZnFe2O4 was synthesized using the hydrothermal method for photocatalytic hydrogen production and methylene blue (MB) degradation in the visible light region. Variation of Cu:Zn ratios transformed the crystalline phase into Cux doped Zn(1-x)Fe2O4, evidenced by the constriction and expansion of crystal lattices. The other phases, CuO, ZnO, and Fe2O3 were identified depending on the degree of Cu dopants, affecting the band gap energy, surface area, and photocatalytic activity. Cu0.25Zn0.75Fe2O4 indicates the high level of Cu dopant into ZnFe2O4 lattices, exhibiting high suppression of charge recombination and transition to a more negative valence band positioned near the hydrogen evolution potential, producing 467.8 µmol/g hydrogen. MB degradation at 97.06 % with a rate constant of 61.4 × 10−3/min was achieved on Cu0.75Zn0.25Fe2O4.