全介孔BiVO4/TiO2核壳异质结纳米纤维构筑及其可见光分解水制氢特性

Currently, semiconductor photocatalytic water splitting for hydrogen production has been considered as one of the active and hot research focuses, owing to their potential ability to harness energy from clean and renewable sources, which might provide a possiblity to compleletly address the problem of environmental pollution and energy shortages. However, it remains a grand challenge to explore the photocatalysts with enough high visible-light-driven catalytic efficiencies. In the present work, directed by the exploration of visible-light driven photocatalyst materials with totally excellent performaces, we will firstly realize the controlled fabrication of thoroughly mesoporous BiVO4/TiO2 core-shell heterostructured nanofibers via a novel strategy, namely, foaming-assisted electrospinning, combining with the atomic layer deposition (ALD) process. The research work of this project will be carried out systematically to characterize the visible-light photocatalytic and photoelectrocatalysis water splitting for H2 production over the BiVO4/TiO2 core-shell nanofibers, clarify and optimize the relationship among the structures, compositions and photocatalytic/photoelectrocatalytic properties. It is promissing that the as-fabricated thoroughly mesoporous BiVO4/TiO2 core-shell nanofibers might take advantage of the enlarged specific surface areas, tailed energy band gaps and improved separation of photon-generated carriers, which lead to the synergetic enhancement of their photocatalytic activities for visible-light-driven hydrogen production. Current work might put forward the exploration of visible-light-driven photocatalysts with excellent performances, and could have scientific significances and potential applications.

半导体光解水产氢技术，具有彻底解决环境污染和能源短缺问题的诱人远景，是当前国际研究的前沿和热点之一。然而，如何实现可见光高效催化产氢，依然是当前该领域面临的主要困难和挑战。本项目拟以综合性能优异的可见光光催化材料研发为导向，基于发泡辅助静电纺丝宏量可控制备全介孔半导体纳米纤维新工艺，结合原子层沉积技术，实现全介孔BiVO4/TiO2核壳异质结纳米纤维的制备及其结构精细调控。相关工作将系统探究其可见光光催化和光电催化分解水制氢特性，阐明BiVO4/TiO2异质结结构、组分与光解水产氢性能之间的相互关系和本质规律，以期集增大比表面积、能带调控和强化光生载流子分离等多种手段于一体，协同强化光解水产氢能力，实现综合性能优异的可见光光催化材料的研发，具有显著的科学意义和潜在的应用前景。

利用半导体太阳能光催化或光电催化分解水制氢，被认为是彻底解决环境污染和能源短缺问题有效手段之一。在半导体光催化材料家族中，BiVO4材料体系因其独特化学稳定性、无毒和合适的禁带宽度，是最具代表性的光催化剂材料之一。然而，传统的BiVO4光催化剂材料受到比表面积偏低的影响，其可见光光催化制氢性能较低。本项目旨在提高BiVO4的光催化剂材料的比表面积，进而提高其可见光光催化产氢活性。综合本项目研究工作，取得如下研究成果：1)采用发泡辅助静电纺丝技术，实现了BiVO4全介孔纳米纤维的可控制备与结构调控, 其比表面积相比传统的BiVO4纳米纤维提高3倍以上；2) 采用原子层沉积技术(ALD)，在BiVO4全介孔纳米纤维的表面包覆TiO2膜，实现了BiVO4/TiO2核壳异质结光催化剂材料的制备。TiO2与BiVO4紧密接触形成异质结，两者之间费米能级的差异，使得BiOV4 在可见光的激发下，产生的高能量电子向TiO2 导带位置迁移，可直接应用于光催化分解水制氢，同时抑制了光生电子和空穴的复合，其可见产氢性能得到强化。在本项目的资助下，目前已发表SCI论文23篇(其中影响因子大于3的18篇，影响因子大于10的3篇)，授权国家发明专利3项，培养硕士研究生2名，博士研究生1名。本项目的实施与完成为开发高效、价廉、环保的可见光响应光催化材料提供了一定实验依据和理论指导，推动其在清洁能源等领域的实际应用，具有显著的科学价值和良好的应用前景。