Developing highly efficient carbon based catalyst for electrochemical advanced oxidation processes (EAOPs) application is significant for environmental remediation. Herein, for the first time, the in-situ metal-free EAOPs with graphite felt cathode modified by N-doped graphene (N-EEGr) was established and demonstrated a superior and reusable catalytic activity for activation of H₂O₂ to OH. N-EEGr-GF was systematically characterized, and its electrocatalytic behavior for oxygen reduction reaction as well as the degradation performance were investigated. N-doping was found not changing the electrochemical generation of H₂O₂, but increasing the catalytic decomposition with a doubled phenol degradation rate. ESR spectra, methanol and benzoquinone capture confirmed the existence of OH and O₂ in EAOPs, while the former played the dominant role. Compared with traditional electro-Fenton (EF), this in-situ metal-free EAOPs demonstrated 4-times higher efficiencies with a more broad suitability upon pH. In view of its competitive advantage in reusability and environmental friendliness without catalysts addition and second pollution, this process can be regarded as the competent substitution of traditional EF for wastewater treatment. This study illustrated insights into the versatile N-EEGr for sustainable activation of H₂O₂ to OH and may shed light on the development of remarkable catalyst for highly efficient metal-free EAOPs.

开发用于电化学高级氧化工艺（EAOP）的高效碳基催化剂对环境修复具有重要意义。在此，首次建立了具有由N掺杂石墨烯（N-EEGr）改性的石墨毡阴极的原位无金属EAOP，并证明了将H ₂ O ₂活化为OH的优异且可重复使用的催化活性。对N-EEGr-GF进行了系统表征，研究了其对氧还原反应的电催化性能以及降解性能。发现N掺杂不会改变H ₂ O ₂的电化学生成，但增加了催化分解作用，苯酚降解率提高了一倍。ESR谱图，甲醇和苯醌捕获证明了EAOP中OH和O ₂的存在，而前者起了主导作用。与传统的电子芬顿（EF）相比，这种原位无金属的EAOP具有4倍的高效率，并且在pH值上具有更广泛的适用性。鉴于其在不添加催化剂和二次污染的情况下在可重复使用性和环境友好性方面的竞争优势，该工艺可被视为传统EF废水处理的有效替代品。本研究中所示的见解到多功能的N- EEGR为h的可持续活化₂ Ò ₂至OH，并可能为高效无金属EAOP的出色催化剂的开发提供启示。