To achieve the full utilization of excess Enteromorpha resources and the effective oxidation of organic contaminants from water, the FeCu composite nanoparticles encapsulated by N-doped graphene layers were produced via the thermal treatment of Enteromorpha-supported urea and metal ions, and used the materials to activate peroxymonosulfate (PMS) for RhB (Rhodamine B) oxidationAn appropriate iron-to-copper ratio is instrumental in enhancing the activation efficacy of the catalyst.The degradation percentage of 20 mg L-1 RhB was almost 100 %, utilizing the ECN@Fe2Cu of 0.1 g L-1.Furthermore, ECN@Fe2Cu exhibits excellent anti-interference properties, reusability, and robust stability throughout the catalytic process.The radical quenching experiment, EPR, and electrochem. tests demonstrate that the main reactive oxygen in ECN@Fe2Cu/PMS/RhB system is 1O2.XPS indicated that Fe0, Fe3C, Cu0, pyridinic N, and graphitic N doped in the carbon layer are the potential active sites.This work demonstrates that a high catalytic activity PMS activator can be produced by doping Fe/Cu/N with Enteromorpha.