The unique TiO2(B)/BiOCl0.7I0.3-P Z-scheme heterojunction effectively degrades and mineralizes the herbicide fomesafen

A Z-scheme heterojunction photocatalyst (TiO2(B)/BiOCl0.7I0.3-P) was constructed (B: bronze phase; BiOCl0.7I0.3: a solid solution of BiOCl and BiOI in a molar ratio of 7:3; P: polyvinylpyrrolidone). The open channels parallel to the b-axis between the axial oxygen atoms in the bronze TiO2, the unique layered structure of BiOCl and the excellent light absorption characteristics of BiOI create excellent conditions for the absorption and utilization of light, the separation and transmission of photo-generated carriers in the photocatalytic process. TiO2(B)/BiOCl0.7I0.3-P can almost completely degrade and mineralize fomesafen within 20 min, and the environmental toxicity of the degradation products is significantly reduced. Combined with high-resolution mass spectrometry, the degradation pathway of fomesafen was proposed. In addition, TiO2(B)/BiOCl0.7I0.3-P can also quickly and effectively degrade phenol and acetaminophen, indicating that it has good universality. To eliminate the harm caused by various herbicides to the ecological environment, photocatalytic technology will play an increasingly important role.