Abstract:

The Ag/BiVO₄&Bi₄V₂O₁₁ composite material with high photocatalytic activity was prepared by hydrothermal reaction and photo-assisted reduction method. The composite material was characterized by XRD，SEM，BET，and its photocatalytic activity to Rhodamine B（RhB） was evaluated by visible light catalytic degradation experiment. The results showed that when the Ag load（mass fraction） of composite material was 0.76%，the degradation rate of 5 mg/L RhB could reach 92.7%. Compared with BiVO₄&Bi₄V₂O₁₁，the degradation effect of RhB by the composite material after Ag deposition increased by 85.9%. The photocatalytic degradation of RhB by Ag/BiVO₄&Bi₄V₂O₁₁ composites was consistent with the first-order kinetic reaction. The enhanced RhB catalytic activity of Ag/BiVO₄/Bi₄V₂O₁₁ composite could be attributed to the fact that Ag deposition not only increased the specific surface area of the composite，but also effectively inhibited the recombination of photogenerated electrons（e^-） and holes（h⁺） due to the surface plasmon resonance （SPR） effect of Ag.

Key words: photocatalysis, Rhodamine B, degradation, photo-reduction, SPR effect

摘要：

利用水热法和光辅助还原法构筑具有高光催化活性的Ag/BiVO₄&Bi₄V₂O₁₁复合材料，通过XRD、SEM、BET表征手段对催化剂的形貌和结构进行表征，利用罗丹明B（RhB）的可见光催化降解实验对材料的光催化活性进行评估。结果表明，当Ag负载量（质量分数）为0.76%时，Ag/BiVO₄&Bi₄V₂O₁₁复合材料对5 mg/L的RhB溶液光催化降解80 min时，RhB降解率为92.7%；相比BiVO₄/Bi₄V₂O₁₁，Ag沉积后的复合材料对RhB的降解效果提高了85.9%；复合材料Ag/BiVO₄&Bi₄V₂O₁₁光催化降解RhB的过程符合一级动力学反应。Ag/BiVO₄/Bi₄V₂O₁₁复合材料光催化降解RhB活性增强可归因于金属Ag的沉积不仅增加了复合材料的比表面积，且Ag的等离子体（SPR）效应有效抑制了光生电子（e^-）和空穴（h⁺）的复合。

关键词: 光催化, 罗丹明B, 降解, 光还原, 等离子体效应

CLC Number: 

• TQ426.91

• X703