Efficient wastewater treatment and simultaneously electricity production using a photocatalytic fuel cell based on the radical chain reactions initiated by dual photoelectrodes.

Efficient conversion of wastewater into clean energy was achieved by applying a radical chain reaction strategy in a solar responsive photocatalytic fuel cell (PFC) system. The system was constructed with two photoelectrodes where ferrous ions were added to enhance the radical reactions for organic pollutants degradation from the surface of electrodes to the whole solution system via coming into a continuous radical chain reaction. The results indicated that the short-circuit current (Jsc) and the power density (JVmax) obtained in the PFC system is up to 1.41-1.60 and 1.52-2.02 times larger than those of the PFC without ferrous ions. Meanwhile, the degradation rate of refractory organics (methyl orange, methylene blue, congo red and tetracycline) increased to 91.98%, 98.57%, 92.36% and 68.09% from 53.61%, 45.38%, 51.09% and 30.65% respectively after 90min operation. The proposed PFC with a radical chain reaction strategy provides a more economical and efficient way for energy recovery and wastewater treatment and implies a possibility of developing much higher efficient PFC system when applying the other electrodes.