pH-Controlled photocatalytic abatement of RhB by an FeWO4/BiPO4 p-n heterojunction under visible light irradiation

摘要

A novel p-n heterostructure of an FeWO4/BiPO4 nanocomposite was designed and synthesized through a simple hydrothermal method. Among all the nanocomposites prepared with different weight percentages of FeWO4, 30% FeWO4/BiPO4 (S3) showed the highest photocatalytic performance for the degradation of Rhodamine B and tetracycline under visible light irradiation. The degradation efficiency of RhB for the S3 sample was 87% under neutral conditions within 300 min but interestingly, at pH 3, 99% degradation efficiency was observed within 30 min with good recyclability. The enhanced photocatalytic performance should be due to the maximum electron-hole pair decoupling efficiency of the S3 catalyst. The mineralization of RhB during the catalytic process was detected by GC-MS. Consequently, based on the experimental results, a possible photocatalytic mechanism over the FeWO4/BiPO4 composite was anticipated, which indicated the substantial potential of the composite for the treatment of textile and pharmaceutical wastewater.