具有空心结构的掺杂型铋基半导体纳米复合材料的设计、构筑及光解水性能研究

Based on the theoretical basis of the enhancement of the photocatalytic activity of the doping and the hollow nanostructures, this project is proposed to design and synthesize a series of different transition-metal ions/nonmetal doped Bi-based semiconductor hybrids with hollow nanostructures as highly efficient photocatalysts for photocatalytic water splitting. By developing facile and mild experimental methods based on different templates or precursors, a variety of ion-doped Bi-based semiconductor nanocomposites will be obtained and then uniform hollow architectures are created by the release of gas products from inside via the in-situ reactions, which results in the integrated synergistic combination of the high-efficiency photocatalysts with hollow-structured architectures. The photocatalytic water splitting efficency of such heterogeneous systems will be investigated in terms of the different doped species selected for combination and the different doped proportions, aiming to establish the correlation between catalytic efficiency and catalyst structures, and therefore complete the evaluation system for the photocatalytic water splitting performance of such hybrid compounds. The research achievements of this project are expected to develop new theory and methodology of synthetic techniques and procedures for various doped Bi-based semiconductor nanocomposite heterogeneous catalysts with hollow structures, advance the crossover study from theory to application of such novel functional hybrid materials, and offer technical reserves to the future industrialization of such promising photocatalysts.

本项目以掺杂改性和构建空心纳米结构可增强光催化性能为理论依据，拟设计、合成一系列具有空心结构的过渡金属离子或非金属掺杂型铋基半导体纳米复合光催化材料。通过简单温和的实验手段，使用不同模板或前驱物在原位转变过程中形成铋基半导体与过渡金属或非金属元素的同步掺杂，同时借助化学转换过程由内而外均匀地形成多孔的空心结构，从而实现了光催化材料的高效杂化与空心构型的完美统一。考察不同掺杂元素、不同掺杂浓度和不同类型空心结构的产品对可见光辐照下的光分解水效率的影响，跟踪光催化剂反应前后的结构特征变化和光解水稳定性，探究其光催化反应作用机制，确定结构-效能间的对应关系。选取典型试样，建立此类复合材料光催化反应动力学模型，完善其光解水性能评价体系。项目的研究结果有助于为掺杂型铋基半导体空心结构光催化剂的合成与调控提供新的理论依据与探索方向，有望促进此类新型复合材料从理论研究到推广应用的跨越式发展。

本项目已按照计划完成了各项研究内容，实现了预期研究目标。设计合成了多孔的Cu掺杂BiVO4(Cu-BVO)空心纳米管光催化剂，通过调节反应条件，实现了Cu-BVO空心纳米管组分和结构的精准调控，组分和结构优化的纳米管显示出优异的光催化水分解产氧性能。同时，揭示了掺杂和空心结构在增强光催化性能中的关键作用。在此基础上，通过对Mo掺杂的BiFeO3纳米管进行碳包覆，提升了空心结构的稳定性，实现了光催化活性和稳定性的同步提高。通过改变表面活性剂浓度，实现了对Bi2Fe4O9纳米片厚度的可控调节。开发了具有普适性且性能超越CoOx的产氧助催化剂。基于上述工作，项目组成员进一步设计了一系列新型高效的掺杂型半导体和具有中空结构的异质结光催化剂，在光催化应用方面取得重要进展。本项目的成功实施，不仅为基于掺杂和空心结构开发新型高效光催化剂提供了设计思想，也为光催化技术的应用提供了一系列新型光催化剂。在基金支持下已发表相关 SCI 期刊论文 39 篇，其中SCI一区24篇，EIS 高被引论文 12 篇，2篇入选热点论文，一篇入选2018年中国百篇最具影响国际学术论文，申请国家发明专利9件，授权2项，并且作为第一完成人获得浙江省自然科学二等奖。