Synthesis of Cs 3 PMo 12 O 40 /Bi 2 O 3 composite with highly enhanced photocatalytic activity under visible-light irradiation

• Published in: Journal of colloid and interface science Vol. 516; p. 304
• Main Authors: Wang, Qi, Liu, Enqin, Zhang, Chenlu, Huang, Siwei, Cong, Yanqing, Zhang, Yi
• Format: Journal Article
• Language: English
• Published: United States 15.04.2018
• Subjects: CsPMo; Polyoxometalate; BiO; Visible light; Phenol degradation
• ISSN: 1095-7103

A novel visible-light-active Cs PMo O /Bi O (CsPMo/Bi O ) composite was prepared by a simple dissolution-precipitation method. The as-prepared samples were characterized by XRD, XPS, FT-IR, SEM, UV-Vis DRS, N adsorption-desorption isotherms and electrochemical analysis. The results revealed that Bi O was successfully modified by trace CsPMo. After the addition of H PMo O acid (HPMo), the surface of Bi O can be roughed. Subsequently, the presence of Cs CO can neutralize the protons of HPMo forming CsPMo precipitate on Bi O . Comparing to naked Bi O and CsPMo, the binary composite exhibited many beneficial characteristics in charge generation and separation, such as formation of p-n heterojunction, decreased band gap, enhanced photocurrent response and greatly reduced charge transfer resistance. The photocatalytic activities of the as-prepared samples were evaluated by the degradation of phenol under visible light. The calculated pseudo-first-order rate constants for phenol degradation were 2.7 and 14.8 times relative to that on Bi O and CsPMo, respectively. Dramatically enhanced photocatalytic performance can be observed when the optimal CsPMo/Bi O composite (2.5% CsPMo) was applied. The major active species involved in the degradation process are in the following order: superoxide radical (O ) > hydroxyl radical (OH) ≈ hole (h ). Besides, the CsPMo/Bi O composite also displayed good stability in cyclic experiments.