Electrocatalytic Generation of Singlet Oxygen via ROS-Mediated Redox Chain Reaction for Efficient Disinfection
Hao Shi, Tianming Wu, Meilin Duan, Jinping Yu, Miao Liu, Xueyun Wen, Lupeng Wang, Yuanhong Xu
Abstract
The risk of harmful microorganisms to ecosystems and human health has stimulated exploration of singlet oxygen ( 1 O 2 )-based disinfection. It can be potentially generated via an electrocatalytic process, but is limited by the low production yield and unclear intermediate-mediated mechanism. Herein, we designed a two-site catalyst (Fe/Mo–N/C) for the selective 1 O 2 generation. The Mo sites enhance the generation of 1 O 2 precursors (H 2 O 2 ), accompanied by the generation of intermediate • HO 2 / • O 2 – . The Fe site facilitates activation of H 2 O 2 into • OH, which accelerates the • HO 2 / • O 2 – into 1 O 2 . A possible mechanism for promoting 1 O 2 production through the ROS-mediated chain reaction is reported. The as-developed electrochemical disinfection system can kill 1 × 10 7 CFU mL –1 of E. coli within 8 min, leading to cell membrane damage and DNA degradation. It can be effectively applied for the disinfection of medical wastewater. This work provides a general strategy for promoting the production of 1 O 2 through electrocatalysis and for efficient electrochemical disinfection.