具有紫外-可见-近红外宽光谱响应的纳米复合中空纤维的制备及其光催化性质研究

项目名称： 具有紫外-可见-近红外宽光谱响应的纳米复合中空纤维的制备及其光催化性质研究

项目编号： No.21201171

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 无机化学

项目作者： 程永亮

作者单位： 中国科学院兰州化学物理研究所

项目金额： 25万元

中文摘要： 本项目针对目前制约TiO2光催化剂应用所存在的太阳光谱响应范围窄和载流子复合几率高的关键问题，以稀土上转换发光纳米材料NaYF4:Ln (Ln为稀土离子)为光敏化剂，通过直接煅烧电纺前驱纤维法制备NaYF4:Ln/TiO2复合中空纳米纤维，并以此为载体负载可见光催化剂Ag@AgX。利用NaYF4:Ln的上转换特性将太阳光中的近红外光转化为紫外光和可见光，结合TiO2与Ag@AgX的协同催化效应促使光生载流子得到有效分离从而抑制激子复合，提高太阳光利用率和光量子效率，制备具有紫外-可见-近红外光宽光谱响应特性和低载流子复合几率的新型高效纳米复合光催化剂。研究纳米复合光催化剂的组成、结构和形貌对其在可见光和近红外光下催化性质的影响，揭示纳米复合光催化剂的能量传递过程与其催化活性之间的内在关系。本项目发展新型高效的纳米光催化剂和推动TiO2基光催化剂在环境修复及能源转化中的应用具有重要意。

中文关键词： 光催化；纳米纤维；静电纺丝；；

英文摘要： Recently, the fabrication of TiO2 based photocatalyst with large solar sunlight harvesting region and low recombination rate of photogenerated carriers has received much more research attention. In this project, we plan to employ rare earth-doped upconvering phosphors NaFY4:Ln (Ln=Yb3+,Er3+,Tm3+,Ho3+) as sensitizing agent to fabricate novel one-dimensional nanocomposite photocatalyst with UV-Vis-NIR response properties via loading visible light photocatalyst Ag@AgX (X=Cl, Br, I) to NaYF4:Ln/TiO2 nanocomposite hollow fibers synthesized by directly annealing of the electrospun composite fibers. The upconversion process of NaYF4:Ln nanocrystals could convert NIR to UV and visible light, which can be harvested by TiO2 and Ag@AgX, respectively. The bandgap match between TiO2 and Ag@AgX facilitates the electron-hole separation and restricts the recombination of photogenerated carriers. These advantages make the nanocomposite photocatalyst exhibit UV-Vis-NIR harvesting and low recombination rate of photogenerated carriers, which would extend photocatalyst harvesting region and enhance the photocatalytic activity. On the basis of the investigation of the influence of the composition, structure and morphology of the photocatalyst on its potocatalytic activity under visible light and near infrared light, we want to reveal

英文关键词： Photocatalytic；nanofibers；electrospinning；；