A visible-light-driven photocatalytic fuel cell/peroxymonosulfate (PFC/PMS) system using blue TiO2 nanotube arrays (TNA) anode and Cu-Co-WO3 cathode for enhanced oxidation of organic pollutant and ammonium nitrogen in real seawater

Antibiotics (or pharmaceuticals) and inorganic nitrogen may coexist in mariculture wastewater, adversely affecting food safety and coastal ecology. Advanced treatment of marine wastewater is of great significance. In this study, simultaneous removal of refractory berberine chloride (BC) and ammonium nitrogen (NH4+-N) was firstly achieved in a visible-light-driven marine photocatalytic fuel cell/peroxymonosulfate (PFC/PMS) system. The modified blue TiO2 nanotube arrays (TNA) anode and Cu-Co-WO3 cathode bridged photo-electrocatalysis, sulfate radical-based oxidation and catalytic chlorination, benefiting both pollutant removal and fuel cell electricity generation. Under optimized conditions (double photoelectrodes, 2.5 mM PMS, R = 500 Ω), the system had an open circuit voltage of 0.57 V, removing 95% of BC and NH4+-N, meeting the discharge standard of mariculture. Natural-sourced CODMn, and inorganic nitrogen in simulated mariculture wastewater were also efficiently removed with power generation. The mechanism involving (photo-)electrocatalytic chlorination and PMS-chlorination theoretically supports the application/optimization of integrated electrochemical technologies for marine pollution control.