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[Display omitted] • The metal–oxygen-carbon bonds boosted interfacial electron transfer. • Ozone utilization efficiency was higher (ΔTOC/ΔO 3 = 1.23–0.68) in Fe 2 Co@CS/EP compared with EP. • Catalytic ozonation played the dominant role in · OH, · O 2 − and 1O 2 generation. • Fe 2 Co@CS/EP presented an enormous potential in wastewater treatment. We fabricated a novel Fe-Co bimetal encapsulated inside carbon aerogel sphere (Fe 2 Co@CS) to improve the electro-peroxone (EP) process. The degradation and mineralization of p -nitrophenol (p -NP) were 100% (15 min) with rate constant of 0.314 min−1 and 83.8% (60 min) in Fe 2 Co@CS/EP, respectively. Fe 2 Co@CS was composed of defective graphite carbon and Fe 2 Co alloy. The presence of metal–oxygen-carbon (M-O-C, M Fe/Co) bonds promoted interface electron transfer from carbon layer towards Fe 2 Co alloy, which was advantageous to the reduction of ≡Fe3+/≡Co3+. Moreover, the Fe-Co synergistic effect also accelerated the interfacial catalytic reaction for activating O 3 and H 2 O 2. The quenching experiment and EPR test indicated that · OH, · O 2 - and 1O 2 were main reactive oxygen species (ROSs). DFT calculations showed that O 3 had lower adsorption energy on Fe 2 Co@CS than H 2 O 2 , manifesting that catalytic ozonation played the key role in ROSs generation. In addition, ozone utilization efficiency in Fe 2 Co@CS/EP (ΔTOC/ΔO 3 = 1.23–0.68) revealed 66-36% increase relative to those of EP (0.74–0.5). Fe 2 Co@CS was an efficient catalyst over a wide pH range (3–11) with permissible iron and cobalt releases. The Fe 2 Co@CS/EP process exhibited high-performance for degrading different pollutants under high salinity condition with coexistence of Cl−, NO 3 − and SO 4 2−. For treating real coal wastewater, the TOC removal was 52.7% at 4 h with low EEC (0.038 kWh (g TOC)−1). This study provided an efficient method for the development of EP in wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxygen doped CNT modified cathode enhanced the efficiency of electro-peroxone (OCNT-EP). • OCNT modified cathode achieved in-situ H 2 O 2 generation, activation and catalytic ozonation. • More hydroxyl and singlet oxygen improved atrazine degradation in OCNT-EP process. • The OCNT-EP process showed excellent stability and wide pH applicability. The oxygen-doped carbon nanotubes coated on the carbon felt acted as cathode to enhance the electro-peroxone (OCNT-EP) process. Owing to the introduction of oxygen-containing functional groups and defect sites, the OCNT modified cathode could achieve in-situ H 2 O 2 generation, activation, and catalytic ozonation in the EP process. The OCNT-EP showed a 2.3-folds apparent first-order rate constant (k) compared with the EP process using CNT cathode (CNT-EP) for atrazine (ATZ) degradation. According to the processes comparison, quenching experiments, electron paramagnetic resonance (EPR) analysis and determination of hydroxyl radical, it was proved that more . OH and 1O 2 were generated by the in-situ H 2 O 2 activation and catalytic ozonation in the OCNT-EP process. Especially, this process improved pollutants degradation under acidic condition for the in-situ H 2 O 2 activation and catalytic ozonation, expanding the pH application range of the EP process with a lower energy consumption (0.10 kWh/g ATZ). What' more, the OCNT modified cathode performed excellent stability with 20 cycle tests, and demonstrated all improved degradation rate (21.7%−78.0%) for various pollutants (carbamazepine, sulfamethazine, phenol and 2,4-dichlorophenol). Therefore, the OCNT-EP process could be considered as a promising and enhanced EP process for wastewater treatment. [ABSTRACT FROM AUTHOR]