Bismuth oxybromide/reduced graphene oxide heterostructure sensitized with Zn-tetracarboxyphthalocyanine as a highly efficient photocatalyst for the degradation of Orange II and phenol

The preparation of heterostructured photocatalysts associating BiOBr, reduced graphene oxide (rGO) and zinc tetracarboxyphthalocyanine (ZnPc(CO2H)4) and their performance for the degradation of the Orange II dye and of phenol are reported. The BiOBr/rGO/ZnPc(CO2H)4(0.25) photocatalyst displays a superior activity than BiOBr and BiOBr/rGO, indicating that ZnPc(CO2H)4 enhances both the visible light absorption and the charge carrier separation, which is confirmed by photoluminescence, photocurrent responses and electrochemical impedance spectroscopy Nyquist plots. Scavenging experiments show that the main active species involved in the degradation of Orange II and phenol are superoxide radicals and holes and a mechanism is proposed. Due to its high stability, the BiOBr/rGO/ZnPc(CO2H)4(0.25) catalyst shows high potential for real environmental remediation.