Critical Roles of Co-doped g-C 3 N 4 /Bi 2 WO 6 in photocatalytic removal of organic pollutants and treating oil field wastewater in EC-MFC

The synergy activity of the heterojunctions photocatalyst can be improved further by including the surface plasmon resonance of single metal atoms. For this aim, a simple calcination and hydrothermal method was used to dope single atom Co on top of the Z-type 10 wt% g-C 3 N 4 /Bi 2 WO 6 heterojunctions which we had tested previously. The optimal Co doping was determined at 0.2 wt% Co/10 wt% g-C 3 N 4 /Bi 2 WO 6 , that it most efficiently degraded (100 mg/L) RhB under visible light irradiation (99.7% in 30 min, kinetic rate constant 0.182 min -1 ). This single-atom doped catalysts (Co/g-C 3 N 4 /Bi 2 WO 6 ) should be most favorably used in treating practical wastewater in EC (electro-chemical)-MFC (microbial fuel cell) system. Its remarkable performance was recorded (96% COD removal and 92.8% TOC removal). The reactive oxidizing species include h + , 1 O 2 , ·O 2 - , e - , and ·OH, they act together leading to the rapid degradation of pollutants. The developed Co-doped ternary catalyst has promising application prospects in pollution control in real world wastewater treatment.