前驱液pH值对TiO_2多级结构纳米纤维材料光催化性能的影响

Effect of precursor solution pH on the photocatalytic activity of TiO_2 multi-structured nanofiber materials

采用模板辅助溶剂热法制备TiO2多级结构纳米纤维材料，用X射线衍射（XRD）、扫描电镜（SEM ）、透射电镜（TEM ）等技术对其结构、形貌进行了表征．以亚甲基蓝（MB）溶液的降解脱色为模型反应，考察了前驱液 Ti4＋／EtOH的p H值（1.98～11.67）对材料光催化性能的影响．结果表明，前驱液p H值不仅影响材料的结构、形貌，而且影响材料表面的荷电性质和光吸收性能，最终影响材料的光催化性能．在较高pH值下所得材料具有的良好光催化性能主要与材料的多级结构、表面负电性质有关．

TiO2 multi‐structured nanofiber materials are prepared via template‐assisted solvothermal method and characterized by X‐ray diffraction （XRD ） , scanning electron microscopy （SEM ） and transmission electron microscopy （TEM） . The photocatalytic degradation of Methylene blue （MB） is used as the model reaction to evaluate the photocatalytic activity of the samples . The results indicate that the pH value of the Ti4＋ /EtOH influences not only the structure and morphology but also the surface charge of the samples and light absorption properties . The good photocatalytic activity of the samples , prepared under higher pH value of the precursor solution Ti4＋ /EtOH ,is mainly ascribed to their multi‐structure and negative charge of the surface .