发展高效的可见光催化剂是太阳能化学利用的一个挑战.本文采用简单的混合方法,制备了WO3和Fe2O3的混合物,研究了该复合氧化物在H2O2存在下光催化降解有机染料X3B的活性.实验表明,催化剂的光催化活性与其煅烧温度和Fe2O3含量有关.最佳煅烧温度和Fe2O3含量分别等于400℃和1.0%(w).根据自由基捕获电子顺磁共振(EPR)波谱分析,复合氧化物产生羟基自由基的量远高于FezOa和WO。我们推测,这种协同效应来源于WO3和Fe2O3之间的电荷转移。从而加快半导体光生载流子的分离和X3B的光催化降解.
Development of a highly active visible-light-driven photocatalyst is a challenge for chemical use of solar energy. In this work, WO3 was simply mixed with Fe2O3, and used thereafter for the photocatalytic degradation of organic dye X3B in the presence of H2O2. It was observed that the composite activity was greatly influenced by the catalyst sintering temperature, and by Fe2O3 content in the mixed oxide. The optimum sintering temperature and Fe203 loading were 400℃ and 1.0% (w), respectively. Through a spin trapping electron paramagetic spectroscopy, it was found that the composite produced a significantly larger amount of hydroxyl radicals, in relative to Fe203 and WO3. It is proposed that the observed synergistic effect between Fe203 and WO3 is due to the charge transfer between the two oxides, improving the separation of the photogenerated charge carriers, and thus accelerating the photocatalytic degradation of X3B.