Selective Production of CO from Organic Pollutants by Coupling Piezocatalysis and Advanced Oxidation Processes

To date, the chemical conversion of organic pollutants into value-added chemical feedstocks rather than CO₂ remains a major challenge. Herein, we successfully developed a coupled piezocatalytic and advanced oxidation processes (AOPs) system for achieving the conversion of various organic pollutants to CO. The CO product stems from the specific process in which organics are first oxidized to carbonate through peroxymonosulfate (PMS)-based AOPs, and then the as-obtained carbonate is converted into CO by piezoelectric reduction under ultrasonic (US) vibration by using a Co₃ S₄ /MoS₂ catalyst. Experiments and DFT calculations show that the introduction of Co₃ S₄ not only effectively promotes the transfer and utilization of piezoelectric electrons but also realizes highly selective conversion from carbonate to CO. The Co₃ S₄ /MoS₂ /PMS system has achieved selective generation of CO in actual complex wastewater treatment for the first time, indicating its potential practical applicability.