Jun Liu,Lei Qiu,Meng-Jie Chang,Bin Yuan,Meng Sun,Si-Meng Fan,Wen-Na Cui,Qian Hui,Fu-Rong Ni,Min-Yu Li,Ya-Qing Li,Zhen-Min Luo
Novel fibrous BiVO 4 /CdS heterostructures were fabricated for photodegradation of Rhodamine B (RhB) dyes. Caterpillar shaped BiVO 4 nanofibers were produced by electrospinning and post calcinations . Controllable quantity of CdS nanoparticles were uniformly decorated on BiVO 4 fiber surface by electrostatic interaction . Both the BiVO 4 nanofibers and CdS nanoparticles present high crystallinity . The integration of CdS can significantly enhance the absorption of visible light and separation efficiency of photo-generated charge in BiVO 4 /CdS composites. As a result, the photocatalytic efficiency and apparent reaction rate constant of the optimized BiVO 4 /CdS-2 display 1.6 and 3 times as high as that of pure BiVO 4 after 120 min irradiation under visible light, respectively. Moreover, the BiVO 4 /CdS-2 nanofibers show good stability for repeated visible light photocatalytic application. The scavengers added photocatalytic experiments indicate the crucial roles of •O 2 − and h + for the degradation process, and a Z-scheme photocatalytic mechanism was proposed for the BiVO 4 /CdS system. Due to the simple and low-cost synthetic method, the fibrous BiVO 4 /CdS catalysts are suitable for practical applications.
Rui Guo,Aiguo Yan,Juanjuan Xu,Botao Xu,Tingting Li,Xuanwen Liu,Tingfeng Yi,Shaohua Luo
BiVO 4 /CdS composites with different morphologies and mass ratios were successfully prepared via a facile deposition-precipitation method by adding different dispersants. Compared with spherical BiVO 4 (BS), sheet-like BiVO 4 nanoarrays (BA) showed higher (020) exposed areas, as confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). X-ray photoelectron spectroscopy (XPS) revealed further details on the microstructure of the composites namely, CdS was deposited on the surface of BiVO 4 forming an S-(111) interface layer. The photocatalytic properties of the samples were tested by studying the degradation of Rhodamine B (RhB) and the sterilization of Escherichia coli ( E. coli ) under visible-light irradiation. The BAC-60 sample showed the best photocatalytic performance among all the catalysts owing to its: (i) improved high separation efficiency of the photo-induced charge carriers and (ii) high exposure activity of the (020) plane. Electrochemical tests with non-equilibrium carrier injection and free radical trapping experiments are introduced to analyze the mechanism, such as the effects of different crystal planes on the photocatalytic reaction and the flow direction of carriers at the CdS–BiVO 4 interface.
Developing cost-effective photocatalysts with efficient electron hole separation efficiency and excellent light absorption performance for the remediation of organic pollutants from wastewater is highly desirable. Herein, a new Z-Scheme Bi/BiVO 4 -CdS heterojunction with leaf-like morphology has been successfully fabricated for the first time and its application as a photocatalyst for the degradation of tetracycline hydrochloride (TCH) has been explored. Compared with BiVO 4 and Bi/BiVO 4 , the as-prepared Bi/BiVO 4 -CdS exhibits improved light absorption capacity and electron-hole separation efficiency, and it has a superior performance of photocatalytic degradation of TCH. The degradation ratio of TCH by Bi/BiVO 4 -CdS based photocatalysis reaches 85.5% within 30 min. The rate constant of TCH degradation for Bi/BiVO 4 -CdS is 1.32 and 1.18 times of the BiVO 4 and Bi/BiVO 4 , respectively. In addition, Bi/BiVO 4 -CdS displays a high stability without obvious decay for its TCH degradation efficiency (<5%) during four recycles. The ESR characterization and reactive species trapping experiments indicates that the generated h + , •O 2 – , and •OH from Bi/BiVO 4 -CdS based photocatalysis are responsible for TCH degradation. Since several intermediates are identified by HPLC-MS, the pathways for Bi/BiVO 4 -CdS based photocatalytic degradation of TCH are proposed.
危险品化学品经营许可证（带存储）