Hydrogen production from water splitting under UV light irradiation over Cu-loaded mesoporous-assembled SrTixZr1-xO3 and SrTixSi1-xO3 nanocrystal photocatalyst

Abstract

Nowadays, the global demand for energy is expected to increase, and the primary source of currently consumed energy is fossil fuels, e.g. petrolum oils, which cause global warming because fossil fuels produce a large amount of CO2. So, renewable and environmentally friendly energy resources are desirable and have tendency to increase in the future. Hydrogen has received great attention for use as an alternative and renewable energy source for internal-combustion engines and fuel cells. Photocatalytic water splitting can produce hydrogen by using solar light as an energy source and water as a feedstock. SrTiO3 is one of the interesting photocatalysts due to its superior physicochemical properties, such as its excellent thermal stability, photocorrosion resistibility, and good structure stability as the host for metal ion doping. The purpose of this work to optimize the composition of mesoporous-assembled SrTixZr1-xO3 and SrTixSi1-xO3 nanocrystals, which were synthesized by a sol-gel process with the aid of a structure-directing surfactant for achieving the highest photocatalytic activity for hydrogen production from water splitting under UV light irradiation with methanol as a hole scavenger. The mesoporous-assembled SrTi0.93Zr0.07O3 and SrTi0.95Si0.05O3 photocatalysts calcined at 700 C were found to show the better the photocatalytic hydrogen production activity than the other SrTixZr1-xO3 and SrTixSi1-xO3 photocatalysts. Moreover, the Cu loadings by photochemical deposition method were found to greatly enhance the photocatalytic activity of the SrTi0.93Zr0.07O3 and SrTi0.95Si0.05O3 photocatalysts.