Facile synthesis of heterojunctions by hydrothermal decoration of CdS on electrospun BiVO_4 nanofibers with boosted photocatalytic activity

摘要

Bismuth vanadate (BiVO_4) is a promising photocatalyst material for photocatalytic degradation of organic pollutions. However, the fast recombination of photo-induced charge and insufficient light absorption often lead to poor photocatalytic performance. Herein, novel fibrous BiVO_4/CdS (BVO/CdS) heterostructures are constructed by uniformly modifying caterpillar shaped electrospun BiVO_4 nanofibers with controllable quantity of CdS nanoparticles through hydrothermal reaction. The absorption of visible light and separation efficiency of photo-generated charge of BiVO_4 are significantly promoted after the decoration of CdS nanoparticles. As a result, the photocatalytic efficiency of the optimized BVO/CdS sample (BVO/CdS-2 stands for the sample synthesized with 0.05 mmol Cd(CH_3COO)_2 and CH_4N_2S) is 90.43%, which is 3.3 times as high as that of pure BiVO_4 after 180 min irradiation under visible light, respectively. Moreover, the .O_2~- and .OH are the predominant active species for the degradation process indicated by scavengers added photocatalytic experiments. Due to the simple, low-cost and controllable synthetic process, the BVO/ CdS heterojunctions are suitable for practical usage.