Heterogeneous catalytic system of photocatalytic persulfate activation by novel Bi2WO6 coupled magnetic biochar for degradation of ciprofloxacin

A novel photocatalyst was synthesized by coupling magnetic biochar (Fe-N-Biochar) with Bi 2 WO 6 , in addition, a heterogeneous catalytic system of persulfate activation with great degradation performance can be built taking advantage of the well photocatalytic activity. It can be determined that Fe-N-Biochar involving Fe 2 O 3 and C 3 N 4 -like biochar can be coupled with Bi 2 WO 6 to synthesize a composite (BW/Fe-N-B), which exhibited the nanoparticle made of stacked nanosheets. It has been confirmed that the heterojunction structure between Bi 2 WO 6 and Fe-N-Biochar and the good electrical conductivity of Fe-N-Biochar can enhance the visible-light response capability of BW/Fe-N-B to boost the separation efficiency of photogenerated electron-hole pairs. Furthermore, the enhanced photocatalytic activity and magnetism of BW/Fe-N-B can effectively activate persulfate to build the heterogeneous catalytic system, degrading 95.18% of ciprofloxacin (CIP) within 30 min. The photogenerated electrons and holes were the main active substances for photocatalytic degradation of CIP, which also played a key role in persulfate activation to produce OHꞏ, O 2 - ꞏ and SO 4 - ꞏ for high-efficiency degrading CIP. This study not only provided a feasible method for the preparation of novel BW/Fe-N-B composites with high efficiency visible-light photocatalytic performance, but also afforded a possible way for the photocatalytic persulfate activation to construct the heterogeneous catalytic system with high-efficiency degradation performance.