三维宏孔n型Si/TiO2纳米线异质结的构建及光电化学性质研究

项目名称： 三维宏孔n型Si/TiO2纳米线异质结的构建及光电化学性质研究

项目编号： No.51502023

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 一般工业技术

项目作者： 杨继凯

作者单位： 长春理工大学

项目金额： 21万元

中文摘要： 环境污染与能源危机已成为威胁人类生存的严峻问题。TiO2在污水处理、空气净化及光解水等方面具有广泛的应用前景。然而其太阳光利用率低、光生电荷载流子分离效率低、比表面积小及分离回收再利用困难等一系列问题限制了它的产业化进程。针对这些问题，我们利用光辅助电化学腐蚀结合水热技术设计构建三维宏孔n型Si/TiO2纳米线异质结，并研究其光电化学性质。通过各种测试手段研究制备条件、形貌、微结构及异质结效应对三维宏孔n型Si/TiO2纳米线异质结的光电催化性能和光解水性能的影响。利用n型Si可吸收可见光、n型Si/TiO2异质结光生电荷载流子的高分离效率、三维结构比表面积大、易于电解液传输及可回收再利用的优点，获得既具有高光电催化活性又具有高光解水活性的新型多功能材料。同时，结合辅助性实验、验证性实验以及理论模拟实验结果，揭示该异质结的光电催化和光解水机理，为其走向实用化提供相关实验数据和相应理论依据。

中文关键词： 异质结；光电化学；宏孔硅；二氧化钛；多功能材料

英文摘要： Global environmental pollution and energy crisis have become increasingly serious issues for human beings to confront in modern society. TiO2 has broad prospect of application in the fields of waste-water treatment, air purification, photochemical water splitting, and so forth, However, the industrial application of TiO2 as the photocatalysts so far is hindered by their drawbacks of the low sunlight utilization, the low photogenerated charge carrier separation efficiency, the low specific surface area, the difficulty of water separation and recycling of TiO2 photocatalyst, and so on. To solve the above problems, we herein plan to fabricate the three-dimensional macroporous n-Si/TiO2 nanowire heterojunction by photo-assisted electrochemical etching and hydrothermal method and its photoelectrochemical properties were researched. The effect of preparation condition, morphology, microstructure and heterojunction effect of three-dimensional macroporous n-Si/TiO2 nanowire heterojunction on photochemical properties for water splitting and photoelectrocatalysis was studied by some measurement methods. It is expected to obtain a new kind of multifunction material with high activity for water splitting and photoelectrocatalysis by taking the advantages of visible-light absorption of n-Si, high photogenerated charge carrier separation efficiency of n-Si/TiO2 heterojunction, the facilitated electrolyte diffusion and high specific surface area of three-dimensional structure, and recycling of photocatalyst. Meanwhile, the photoelectrochemical mechanism of water splitting and photoelectrocatalysis of the heterojunction would be proposed by combining the results of verification experiments and theoretical simulation experiments. This work provides a useful platform for the design and fabrication of three-dimensional multifunction material that would exhibit excellent performance in the photoelectrochemical applications.

英文关键词： Heterojunction;Photoelectrochemistry;Macroporous Si;TiO2;Multifunction material