2023-04-26
Lately, results of the research team led by Professor Wang Hui from College of Environmental Science and Engineering entitled "Enhanced electrocatalytic cathodic degradation of 2,4-dichlorophenoxyacetic acid based on a synergistic effect obtained from Co single atoms and Cu nanoclusters" was published in top journal of environmental circle Applied Catalysis B: Environmental (IF=24.319). The first author of the article is Liu Lu, graduate student from College of Environmental Science and Engineering, and Beijng Forestry University is the signature unit of the first author.
Electrochemical reduction-oxidation is an environmentally-friendly process of degrading 2,4-dichlorophenoxyacetic acid (2,4-D). However, the design of electrocatalysts having reductive dechlorination and oxygen-specific active sites remains challenging. In the present study, catalytic cathodes were made from single Co atoms and Cu nanoclusters on nitrogen-doped carbon to enhance the degradation of 2,4-D through a synergistic mechanism. In this process, 2,4-D was dechlorinated on the Cu nanoclusters and then oxidized by ·OH radicals produced by the conversion of O2 on the Co atoms. The Cu nanoclusters served as both conductive bridges and 2,4-D adsorption sites to improve the electron transfer of the circuit and so accelerate the direct electron transfer associated with dechlorination. The single Co atoms first reduced O2 to H2O2 and then continuously catalyzed the decomposition of this H2O2 to form ·OH. As a result of the synergistic combination of these two effects, complete efficient dechlorination and 93.4% total organic carbon removal were achieved after 2 h. The kinetics constant for this reaction was determined to be 546.4 min−1·gmetal−1, indicating exceptional performance relative to previous reports of organic pollutant degradation. This study demonstrates the rational design of a bifunctional electrocatalyst and elucidates the electron transfer pathway and O2 activation mechanism associated with 2,4-D removal by electrochemical reduction-oxidation. This process is likely to have potential applications in the remediation of polluted water.
This work was supported by the National Natural Science Foundation of China (No. 52270057 and 52070015), Beijing Natural Science Foundation of China (No. 8222061), and Beijing Forestry University Outstanding Young Talent Cultivation Project (No. 2019JQ03007).
Paper link: https://doi.org/10.1016/j.apcatb.2023.122748
