基于光子晶体设计的三维有序大孔结构半导体光电极材料

The conversion of solar energy into hydrogen represents an attractive but challenging alternative for photoelectrochemical cells.? Three-dimensionally ordered macroporous semiconductor photoelectrodes will be prepared by colloidal crystal templating methods. Photonic-crystal-based optical coupling offers a unique way of light-matter interaction to increase the light harvesting, especially around the absorption edge of a semiconductor. The light in a photonic crystal undergoes strong coherent multiple scattering and travels with very low group velocity near the stop band edges, referred to as slow light. If the inverse opal photoelectrode is designed to be resonant with a specific light frequency around its electronic absorption edge, the interaction of the photoelectrode with that frequency of light may be greatly improved, thus enhancing its IPCE. .In this project, our studies will be focused on: (1) developing new semiconductor photoelectrodes with high efficiency. (2) design and preparation of colloidal crystal templating. (3) preparation of large-area three-dimensionally ordered (3DOM, or inverse opal) photoelectrodes; (4) the slow-light effects of 3DOM on the photoelectrochemical properties.

半导体光电极材料可以利用太阳能分解水制氢，这已成为当前学术界的研究热点之一。本项目利用光子晶体胶体模板制备三维有序大孔结构（3DOM）半导体光电极。通过控制胶体微粒直径大小来调节三维有序大孔结构（3DOM）中慢光效应出现的位置，使得慢光位置与半导体光电极材料的吸收边接近，这样可以提高带边吸收，从而提高光电极量子转换效率。本项目主要研究：（1）新型半导体光电极材料的探索；（2）胶体晶体模板的设计和可控组装，制备大面积高度有序的光子晶体（胶体晶体）；（3）研究3DOM结构半导体光电极的合成方法，制备出大面积高度有序的3DOM；（4）研究3DOM光电极的光电化学性能，尤其是慢光效应对光电化学性能的影响规律。

本项目探索了高效半导体光电极，获得了高效光阳极Ta3N5和高效光阴极。利用光子晶体胶体模板制备三维有序大孔结构半导体光电极（例如WO3、TiO2等），阐明3DOM 光电极的光电化学性能，尤其是慢光效应对光电化学性能的影响规律。阐明了多孔结构对光吸收、电荷分离效率、表面电荷注入效率的影响规律。。提出了一种抑制表面电荷复合的新思路。利用晶面协同效应提高了光催化效率。共发表SCI论文36篇，申请发明专利3项。