Development of solar-light-driven photocatalyst for energy and environmental application

Abstract

Efficient utilization of solar energy could relieve many energy and environmental problems. Overall photocatalytic water-splitting using solar energy has received enormous attention for production of renewable hydrogen from water. Recently, a novel Ag3PO4 photocatalyst with band gap of 2.43 eV, possessing remarkable photocatalytic ability for organic dye degradation has been reported. In this work a highly efficient photocatalyst P/Ag/Ag2O/Ag3PO4/TiO2 has been synthesized and characterized by SEM, TEM, XRD, EDS, XPS, UV-vis and PL respectively. The results suggest that a highly efficient photocatalyst P/Ag/Ag2O/Ag3PO4/TiO2 has been synthesized successfully and performed strong absorption band in visible-light region, high separation efficiency of photo excited electron-hole pairs and small band gap (approximately 2.2 eV). On the other hand, Rodamine B (RhB) and methanol are representative organic compounds that can be used as sacrificial reagent for increasing water-splitting efficiency. For the purpose of identifying the possibility of generating oxygen and hydrogen by the as-prepared P/Ag/Ag2O/Ag3PO4/TiO2 under simulated solar irradiation, the accumulated amount of oxygen and hydrogen was evaluated. The results showed that the optimal conditions of water-splitting process by using the mixture of RhB and methanol under solar light is 20% of methanol, 1.0 ppm of RhB and 0.100 g/L of catalyst dosage. In summary, as-prepared P/Ag/Ag2O/Ag3PO4/TiO2 composite has the potential for environmental and energy application under solar light.