Tao Ran, Li Xinghua, Li Xiaowei, Liu Shuai, Shao Changlu, Liu Yichun
Centre for Advanced Optoelectronic Functional Materials Research, and Key Laboratory of UV-Emitting Materials and Technology (Northeast Normal University), Ministry of Education, Changchun 130024, PR China.
Centre for Advanced Optoelectronic Functional Materials Research, and Key Laboratory of UV-Emitting Materials and Technology (Northeast Normal University), Ministry of Education, Changchun 130024, PR China.
J Colloid Interface Sci. 2020 Jul 15;572:257-268. doi: 10.1016/j.jcis.2020.03.096. Epub 2020 Mar 27.
Designing and constructing one-dimensional (1D) discrete heterojunctions comprise an ideal strategy to improve the charge-separation efficiency and enhance the photocatalytic activities of semiconductor materials. Here, a novel architecture of discrete heterojunction nanofibers (DH-NFs) was obtained by growing BiWO nanosheets (NSs) on electrospun BiFeO nanofibers (NFs) via solvothermal technology. The charge-separation efficiency of BiFeO/BiWO DH-NFs was approximately 2 times higher than that of BiFeO NFs and BiWO NSs. As expected, the BiFeO/BiWO DH-NFs exhibited enhanced photocatalytic activities for oxygen evolution and RhB degradation. The reaction rates of BiFeO/BiWO DH-NFs for oxygen evolution and RhB degradation were 18.3 and 36.7 times higher, respectively, than those of BiFeO NFs, and 31.9 and 8.7 times higher than those of BiWO NSs, respectively. The improved charge-separation efficiency and enhanced photocatalytic activities of BiFeO/BiWO DH-NFs could be attributed to the following three points. The 1D heterojunctions could realize the separation and axial transport of photogenerated charges. The discrete structure could facilitate the spatial separation of redox reaction sites as well as photogenerated charges. The high surface area of BiFeO/BiWO DH-NFs might provide more active sites for photocatalytic reaction. Moreover, the BiFeO/BiWO DH-NFs possessed good recycling performance owing to the magnetic-separable property derived from the ferromagnetic behavior of BiFeO.
设计和构建一维（1D）离散异质结是提高电荷分离效率和增强半导体材料光催化活性的理想策略。在此，通过溶剂热技术在静电纺丝的BiFeO纳米纤维（NFs）上生长BiWO纳米片（NSs），获得了一种新型的离散异质结纳米纤维（DH-NFs）结构。BiFeO/BiWO DH-NFs的电荷分离效率比BiFeO NFs和BiWO NSs高出约2倍。正如预期的那样，BiFeO/BiWO DH-NFs对析氧和RhB降解表现出增强的光催化活性。BiFeO/BiWO DH-NFs析氧和RhB降解的反应速率分别比BiFeO NFs高18.3倍和36.7倍，分别比BiWO NSs高31.9倍和8.7倍。BiFeO/BiWO DH-NFs电荷分离效率的提高和光催化活性的增强可归因于以下三点。一维异质结可以实现光生电荷的分离和轴向传输。离散结构可以促进氧化还原反应位点以及光生电荷的空间分离。BiFeO/BiWO DH-NFs的高表面积可能为光催化反应提供更多活性位点。此外，由于BiFeO的铁磁行为产生的磁分离特性，BiFeO/BiWO DH-NFs具有良好的循环性能。
