Design of a direct Z-scheme photocatalyst: Preparation and characterization of Bi2O3/g-C3N4 with high visible light activity

作者：Zhang, Jinfeng; Hu, Yingfei; Jiang, Xiaoliang; Chen, Shifu^*; Meng, Sugang; Fu, Xianliang

来源：Journal of Hazardous Materials, 2014, 280: 713-722.

DOI：10.1016/j.jhazmat.2014.08.055

• Z-scheme photocatalyst
• Bi2O3/g-C3N4
• Preparation
• Characterization
• Mechanism

A direct Z-scheme photocatalyst Bi2O3/g-C3N4 was prepared by ball milling and heat treatment methods. The photocatalyst was characterized by X-ray powder diffraction (XRD), UV-vis diffuse reflection spectroscopy (DRS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) surface areas, photoluminescence technique (PL), and electron spin resonance (ESR) technology. The photocatalytic activity was evaluated by degradation of methylene blue (MB) and rhodamine B (RhB). The results showed that Bi2O3/g-C3N4 exhibited a much higher photocatalytic activity than pure g-C3N4 under visible light illumination. The rate constants of MB and RhB degradation for Bi2O3(1.0 wt.%)/g-C3N4 are about 3.4 and 5 times that of pure g-C3N4, respectively. The migration of photogenerated carriers adopts a Z-scheme mechanism. The photoexcited electrons in the CB of Bi2O3 and photogenerated holes in the VB of g-C3N4 are quickly combined, so the photoexcited electrons in the CB of g-C3N4 and holes in the VB of Bi2O3 participate in reduction and oxidation reactions, respectively. O-center dot(2)-, (OH)-O-center dot and h(+) are the major reactive species for the Bi2O3/g-C3N4 photocatalytic system.

• 出版日期2014-9-15
• 单位安徽科技学院