Ultrafast self-assembly Fe2O3 nanoparticles confined in carbon layers toward robust heterogeneous electro-Fenton reaction

Heterogeneous electro-Fenton (EF) is a promising advanced oxidation process for refractory wastewater treatment. However, typical calcination or hydrothermal method for heterogeneous EF cathode fabrication is time-consuming, energy-consuming, or harmful to the environment. High-temperature shock (HTS) technique is a novel and rapid material synthesis method with the advantages of low-cost, eco-friendly. In this study, the electrodes named Fe2O3@C/carbon cloth (Fe2O3@C/CC), were synthesized by HTS for the first time within an extremely short time (∼5 s). The Fe2O3 nanoparticles with an average diameter of 61.90 ± 15.09 nm are uniformly dispersed on carbon cloth (CC) with the confinement and protection of the carbon layers. The as-prepared Fe2O3@C/CC cathode exhibited excellent electrocatalytic properties in the EF system. The removal efficiency of methylisothiazolinone (MIT) could reach 90.60 ± 1.70% in 40 min at a low current density of 1.11 mA cm−2 under the oxidation of the hydroxyl radical. In addition, the degradation pathways of MIT were further studied. According to the results of theoretical calculation, the –S–N– bond is the primary active site attacked during MIT degradation process. Therefore, heterocyclic loop opening is the main pathway of MIT degradation. HTS is an ultrafast and convenient potential technique compared with other cathode synthesis methods.