球形Cu_2O修饰Bi_2WO_6层状微球的制备及其光催化制取氢气和烷烃的研究

Synthesis of Bi_2WO_6 Hierarchical Microsphere Modified by Cu_2O Sphere and Its Photocatalytic Production of Hydrogen and Alkanes

采用水热法制备了Bi_2WO_6层状微球,通过还原沉淀法在Bi_2WO_6层状微球内部薄片表面修饰纳米球形Cu_2O而制备Cu_2O/Bi_2WO_6复合催化剂。利用X-射线衍射(XRD)、场发射扫描电子显微镜(FESEM)、透射电子显微镜(TEM)、紫外-可见漫反射光谱(UV-vis DRS)、荧光光谱(PL)等对复合光催化剂的晶体结构、形貌、光响应性能等进行表征。在Cu_2O/Bi_2WO_6中,100 nm左右Cu_2O不均匀地附着在1.5μm Bi_2WO_6层状微球的内部的纳米薄片上。通过Cu_2O的复合,可以显著提高Cu_2O/Bi_2WO_6对紫外-可见光谱的吸收能力、光生电子-空穴对的分离效率及光催化活性。以丙酸为电子供体,考察了紫外光照射下Cu_2O/Bi_2WO_6分解水制备氢气和烷烃的性能,结果表明:5wt%Cu_2O/Bi_2WO_6的光催化产生氢气和烷烃的性能最佳。

Hierarchical microsphere was prepared by a hydrothermal method,then modified with Cu2O sphere by a reduction-precipitation method to obtain Cu2O/Bi2WO6 composites. Phase structure,morphology and optical response property were characterized by XRD,FESEM,TEM,UV-vis DRS and PL. In Cu2O/Bi2WO6 composite,100 nm Cu2O spheres were nonuniformly adhered to nanoplates of 1. 5μm hierarchical microsphere. Modification with Cu2O could considerably enhance absorbing ability of ultraviolet-visible light,separation efficiency of photogenerated electron-hole pairs and photocatalytic activity. Using propionic acid as electron donor,performances for production of hydrogen and alkanes via water-splitting process over Cu2O/Bi2WO6 composites have been investigated. Results showed that 5wt%Cu2O/Bi2WO6 exhibited better performance for photocatalytic production of hydrogen and alkanes.