CdS-sensitized K<sub>2sub>Ti<sub>4sub>O<sub>9sub> composite for photocatalytic hydrogen evolution under visible light irradiation
- 作者：Wenquan Cui<sup> ; sup><sup>wkcui@163.comsup> ; Shanshan Ma ; Li Liu ; Jinshan Hu ; Yinghua Liang
- 关键词：CdS ; K2Ti4O9 ; Precipitation ; Photo-catalysis ; Surface deposition
- 刊名：Journal of Molecular Catalysis A ; Chemical
- 出版年：2012
- 期刊代码：57_13811169
- 类别：ch
- 出版时间：July, 2012
- 卷：359
- 期：Complete
- 页码：35-41
- 文件大小：1033 K
摘要
CdS-sensitized K<sub>2sub>Ti<sub>4sub>O<sub>9sub> composite photo-catalysts (hereafter designated as CdS/K<sub>2sub>Ti<sub>4sub>O<sub>9sub>) were prepared by a facile deposition-precipitation method. The samples were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), ultraviolet-visible diffuse reflectance spectra (UV-vis DRS), and X-ray photoelectron spectroscopy (XPS). The photo-catalytic activities for hydrogen evolution were investigated under visible light irradiation. The CdS particles, which were scattered on the surface of K<sub>2sub>Ti<sub>4sub>O<sub>9sub>, had a relative uniform size distribution around approximately 50 nm, and the absorption edge of K<sub>2sub>Ti<sub>4sub>O<sub>9sub> shifted to the visible light region after the deposition of CdS. The composite photo-catalyst loaded with 25 wt.%CdS synthesized via precipitation method showed the highest photo-catalytic activity. The photocatalytic reaction parameters, such as the dosage of catalyst, and concentrations of sacrificial reagents, were studied and optimized. The mechanism of separation of the photo-generated electrons and holes at the CdS/K<sub>2sub>Ti<sub>4sub>O<sub>9sub> composite was also discussed.