Layered double oxide/copper foam actuates dielectric barrier discharge plasma via electron transport: Exploring the reactive species evolution and diuron disassembly routes

Dielectric barrier discharge plasma (DBDP) is a promising advanced oxidation process for water contaminants degradation relying on the coexistence of multiple reactive species. Herein, by introducing carrier foam copper (CuF), a high catalytic activity ternary layered bimetallic oxide (CoFe-LDO/CuF, CFOC) was synthesized. The evolution process (structure-catalytic function) from layered bimetallic hydroxide (CoFe-LDH/CuF, CFHC) to LDO was explored. Phenylurea herbicide diuron (DUR) was efficiently degraded (> 99 %) via the synergistic effects between DBDP and CFOC within 25 min. As an electron transport substrate, CuF promotes the valence circulation (Fe(Ⅲ)/Fe(Ⅱ) and Co(Ⅲ)/Co(Ⅱ)), guaranteeing the catalysis sustainability and surface Cu2O helping the generation of reactive oxygen species. The efficacy of multiple active species in DUR disassembly was systematically explored, and the routes of demethylation and deamination are the dominant paths in DUR degradation. The study of synthetic tunable LDO composite, active species reaction, and DUR degradation pathways will expand the applications of DBDP.