Electrocatalyst and mechanistic elucidation of NiMn-LDH/MnO2(NML)-Fe/C-N composite in 3D electrode system for enhanced degradation of halogenated organic disinfection byproducts

The design and catalytic potential of materials with simultaneously oxidation and reduction performance remains underexplored, particularly in three-dimensional electrochemical systems. This study developed a carbon nanosheet framework with iron insertion and nitrogen doping, as the skeleton for the deposition of. nickel‑manganese metal mixture. Advanced characterization confirmed that the addition of Fe/C-N skeleton can improve morphology and specific surface, which in turn enhances electronic conductivity and degradation efficiency. Electron paramagnetic resonance (EPR) and density functional theory (DFT) calculations certify that the Fe/C-N skeleton can enhance the electron supply capacity and thereby accelerate the generation and stabilization of •H and •OH species during the reaction. Under optimal conditions, the system achieved a maximum Chloracetamide (MCAcAm) degradation rate of 68.86 % and good stability. Moreover, in practical tests using industrial wastewater pre-treated with chlorination, the composite showed exceptional efficiency, achieving 86.14 % chemical oxygen demand (COD) and 74.01 % total organic carbon (TOC) removal within 1 h. These results highlight the potential of NiMn-LDH/MnO 2 -Fe/C-N (Name it NML-Fe/C-N) for practical wastewater treatment and provide valuable insights into the design of advanced electrode materials and the mechanisms of electrocatalytic degradation.