Photocatalysis International Research Center, Research Institute for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan.
ORC Manufacturing Co., Ltd., 4896 Tamagawa, Chino, Nagano 391-0011, Japan.
Molecules. 2018 Nov 27;23(12):3095. doi: 10.3390/molecules23123095.
There is a need for highly efficient photocatalysts, particularly for water purification. In this study, we fabricated a mesoporous TiO₂ thin film on a boron-doped diamond (BDD) layer by a surfactant-assisted sol-gel method, in which self-assembled amphiphilic surfactant micelles were used as an organic template. Scanning electron microscopy revealed uniform mesopores, approximately 20 nm in diameter, that were hexagonally packed in the TiO₂ thin film. Wide-angle X-ray diffraction and Raman spectroscopy clarified that the framework crystallized in the anatase phase. Current⁻voltage (I⁻V) measurements showed rectification features at the TiO₂/BDD heterojunction, confirming that a p⁻n hetero-interface formed. The as-synthesized mesoporous TiO₂/BDD worked well as a photocatalyst, even with a small volume of TiO₂ (15 mm × 15 mm × c.a. 1.5 µm in thickness). The use of deep UV light (λ = 222 nm) as a light source was necessary to enhance photocatalytic activity, due to photo-excitation occurring in both BDD and TiO₂.
需要高效的光催化剂，特别是用于水净化。在这项研究中，我们通过表面活性剂辅助的溶胶-凝胶法在掺硼金刚石（BDD）层上制备了介孔 TiO₂ 薄膜，其中自组装的两亲性表面活性剂胶束用作有机模板。扫描电子显微镜显示出均匀的介孔，直径约为 20nm，在 TiO₂ 薄膜中呈六方排列。广角 X 射线衍射和拉曼光谱表明，该骨架在锐钛矿相中结晶。电流-电压（I-V）测量表明在 TiO₂/BDD 异质结处具有整流特性，证实形成了 p-n 异质界面。即使 TiO₂ 的体积很小（厚度约为 1.5 µm，尺寸为 15mm×15mm），所合成的介孔 TiO₂/BDD 作为光催化剂也能很好地工作。由于在 BDD 和 TiO₂ 中都发生光激发，因此需要使用深紫外光（λ=222nm）作为光源来增强光催化活性。
