Redox synergy for efficient and rapid detoxification and degradation of chlorinated pollutants

The electrocatalytic hydrodechlorination (EHDC) technology using a palladium (Pd) cathode to remove chlorinated pollutants has a slow reaction rate, did not mineralize pollutants efficiently, and the Cl⁻ produced during the process poisons the Pd. To solve the above problems, an electron-deficient Pd_0.2-Ti₃C₂T_x/CP cathode that was enriched with a large number of Pd-O bonds was prepared by anchoring Pd to Ti₃C₂T_x through electronic metal-support interaction (EMSI). The Pd_0.2-Ti₃C₂T_x/CP cathode removed Cl⁻ from chlorinated pollutants by EHDC reaction, and the Pt anode oxidized Cl⁻ to generate oxidizing radicals for synergistic degradation of chlorinated pollutants. Degradation experiments proved that efficient degradation of various chlorinated pollutants (turnover frequency (TOF) reached 2.38 min⁻¹) and extremely low electrical energy consumption (E_EO, 0.0279 kWh/m³/order) by the redox synergy. The quenching experiments and theoretical calculations demonstrated that cathodic rapid dechlorination and anodic oxidation of Cl-related radicals synergistically achieved rapid degradation of pollutants, and the pathways and reaction sites for degradation of pollutants by radicals and electron were explored. This was a novel strategy for rapid and efficient degradation of chlorinated pollutants in water through redox synergy system.