ZnCdS-BiFeO₃ heterojunction loaded with cobalt catalyst boosting photoelectrocatalytic hydrogen evolution

The advancement of a Z-scheme photoelectrochemical (PEC) system for hydrogen production and water splitting holds significant promise in addressing the escalating global energy crisis. In this study, a ternary Co-ZnCdS-BiFeO₃ Z-scheme composite photocatalyst was used. By optimizing the ratio of BiFeO₃/ZnCdS, the photocatalytic activity of the material is enhanced, while enhancing the electron transfer efficiency and strengthening the stability of the photoelectric cathode. The Co(dmgBF₂)2(H₂O)₂ was selected as the co-catalyst to further improve the electron-hole separation efficiency and photocorrosion resistance. Under visible light irradiation, the hydrogen production rate of the PEC system can reach 4.03 mmol g⁻¹ h⁻¹. Under optimal conditions, applying a bias voltage of −0.1 V vs. RHE can produce −38.5 µA cm⁻². The photocatalytic current density of is as high as 13 times that of pure ZnCdS, greatly improving the hydrogen production efficiency and stability of the photocatalyst. The study offers a novel benchmark for the development of a high efficiency Z-scheme photocatalyst designed for water splitting and provides new insights into intrinsic resistance through PEC analyses. (Figure presented.)