具有纳米结构的TiO_2纤维光催化氧化活性

Photocatalysis oxidation reactivity of nanostructured TiO_2 fiber

研究了具有纳米结构,高比表面的锐钛矿TiO2纤维在光催化降解苯酚体系中的氧化性能,发现其活性与P25相当;通过加羟基自由基猝灭剂证实了羟基自由基(HO.)对苯酚降解的贡献;而通过加空穴猝灭剂则观察到明显的空穴(h+)效应。并通过K I氧化反应进一步研究了催化剂表面上的空穴效应,结果表明,TiO2纤维上的光生空穴比P25稳定,其空穴量子产率是后者的3.3倍。

The photocatalytic reactivity of nanostructured TiO2 fiber with high specific surface area in phenol system has been investigated. The results show that TiO2 fiber has good photocatalysis properties equivalent to P25. Because the morphology of the nanoporous particles in the micrometer-size range is favorable for separation, TiO2 fiber is a good candidate for the application of industry. The contribution of hydroxyl free radical （ HO·） in the process of phenol degradation was confirmed by adding HO. scavengers and hole effect was observed by adding hole scavengers. Furthermore, the quantum yield of hole generation during TiO2 fiber photocatalysis estimated by iodide ion oxidation is about 3.3 times higher than that of P25 with the absence of O2. Compared with the result of photocatalysis experiment when dissolved O2 exists, it demonstrates the higher stability of holes of TiO2 fiber which may arise from the elaborating structure of TiO2 fiber.