State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, 430070, PR China.
Dalton Trans. 2010 Apr 14;39(14):3420-5. doi: 10.1039/b924584g. Epub 2010 Mar 2.
Carbon-modified Bi(2)WO(6) (C-Bi(2)WO(6)) nanostructures were synthesized via a hydrothermal process in the presence of glucose followed by the calcination in Ar gas at 500 degrees C. The morphologies and crystallinity of Bi(2)WO(6) and the nature of carbon in the composites obtained with different glucose amounts were characterized. Raman spectrum analysis, electron microscopy results and light absorption of C-Bi(2)WO(6) at wavelengths larger than 450 nm clearly confirmed the carbon modification. Further results indicated that glucose did not affect the final crystalline structure or the band gap of Bi(2)WO(6), but it had great influences on the photocatalytic activity of Bi(2)WO(6) towards rhodamine-B (RhB) degradation. When the glucose amount was less than 0.04 g, the photoactivity was enhanced step by step with an increase in the glucose amount. The improved photocatalytic performance could be ascribed to the enhanced photogenerated electron-hole separation and more RhB adsorption associated with carbon. However, when the glucose amount was higher than 0.04 g, the photocatalytic property dramatically decreased due to the severe absorption of almost incident light by carbon, which hindered the accessibility of light to Bi(2)WO(6). Our work provides an alternative way to improve the photoactivity of Bi(2)WO(6) nanomaterials.
碳修饰的 Bi(2)WO(6) (C-Bi(2)WO(6)) 纳米结构是通过在葡萄糖存在下的水热过程合成的，然后在 Ar 气体中于 500°C 下煅烧。研究了不同葡萄糖用量下获得的 Bi(2)WO(6)的形貌和结晶度以及复合材料中碳的性质。拉曼光谱分析、电子显微镜结果和 C-Bi(2)WO(6)在 450nm 以上波长的光吸收清楚地证实了碳的修饰。进一步的结果表明，葡萄糖不影响 Bi(2)WO(6)的最终结晶结构或带隙，但对 Bi(2)WO(6)对罗丹明 B (RhB)降解的光催化活性有很大影响。当葡萄糖用量小于 0.04g 时，随着葡萄糖用量的增加，光活性逐步增强。改进的光催化性能可以归因于增强的光生电子-空穴分离和与碳有关的更多 RhB 吸附。然而，当葡萄糖用量高于 0.04g 时，由于碳几乎完全吸收了入射光，光催化性能急剧下降，这阻碍了光到达 Bi(2)WO(6)的通道。我们的工作为提高 Bi(2)WO(6)纳米材料的光活性提供了一种替代方法。
