材料期刊网

Homogenous and heterogeneous production of hydrogen via photo-dissociation of water has been achieved with visible range solar radiation without any external potential at room temperature. Potassium ferrocyanide as a solvated-electron supplier and electron exchanger in basic buffers was used as a homogenous media for hydrogen production. Aqueous colloidal solutions of p-type Fe₂O₃ doped with MgO (Fe_1:8Mg_0:2O₃) or with ZnO (Fe_1:9Zn_0:1O₃) suspensions in ferrocyanide solutions were used as heterogeneous media for hydrogen generation by reduction of ferricyanide. The effects of the hole-scavengers such as oxo-anions and solvated-electron- suppliers were investigated. Results showed that Fe₂O₃ doped with ZnO was more efficient than that doped with MgO. The studies also showed that the aqueous nano-systems we used retained their stability as indicated by the reproducibility of their photocatalytic activities. Solar radiated assemblies of doped Fe₂O₃/[Fe(CN)₆]⁻₄ sustained cyclic systems for continuous hydrogen production.