| Cr掺杂对K2La2Ti3O10光催化活性的影响 |
| Photocatalytic Activity of K2La2Ti3O10 Doped with Cr |
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| 摘要: 通过溶胶-凝胶法制备了层状钙钛矿结构的K2La2Ti3O10及Cr掺杂的K2La2Ti3O10，采用X-射线衍射(XRD)、紫外可见漫反射光谱(DRS)、X射线光电子能谱(XPS)等对K2La2Ti3O10及Cr掺杂K2La2Ti3O10进行了表征。以I-为电子给体、分别在紫外和可见光辐射下研究了K2La2Ti3O10及Cr掺杂K2La2Ti3O10光催化分解水的产氢活性。采用第一性原理，计算了Cr掺杂对K2La2Ti3O10半导体能带结构和态密度的影响，从电子结构的变化揭示了掺杂引起光催化活性差异的原因。结果表明，Cr的掺入能够改善和提高K2La2Ti3O10的光解水的产氢活性；Cr改善和提高K2La2Ti3O10的光解水的产氢活性存在一个最佳的掺杂浓度；当Cr与Ti的物质量的比为0.02∶1时，紫外光催化分解水产氢速率为1 500 μmol·L-1·h-1，可见光催化分解水产氢速率为83.6 μmol·L-1·h-1，分别为K2La2Ti3O10掺杂改性前产氢速率的26和5倍。 |
| 关键词: K2La2Ti3O10 光催化活性 氢气 第一性原理 |
| 基金项目: |
| Abstract: The layered perovskite type oxides, K2La2Ti3O10 and K2La2Ti3O10 doped with Cr were prepared by sol-gel method and were characterized by XRD, UV-Vis diffused reflectance spectroscopy (DRS) and XPS. The photocatalytic activity for water splitting of K2La2Ti3O10 and K2La2Ti3O10 doped with Cr was investigated with I- as electron donor catalyst under ultraviolet and visible light irradiation, respectively. The electronic structure of K2La2Ti3O10 doped with Cr was analyzed by the first principle calculation, which reveals the photo responses in the visible region and the improvement of the photocatalytic activity for hydrogen production. The optimum doping concentration of Cr was found to be 0.02∶1 (Cr∶Ti) when K2La2Ti3O10 was used as photocatalyst with I- as electron donor. The hydrogen production rate was 1 500 μmol·L-1·h-1 under ultraviolet irradiation and 83.6 μmol·L-1·h-1 under visible light irradiation, which was 26 and 5 times that of undoped K2La2Ti3O10 photocatalyst, respectively. |
| Keywords: K2La2Ti3O10 photocatalytic activity hydrogen the first princiles calculation |
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| 杨亚辉,陈启元,尹周澜,李洁.Cr掺杂对K2La2Ti3O10光催化活性的影响[J].无机化学学报,2007,23(5):771-777. |
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