A novel cathode of macroporous graphene aerogel (GA) with high specific surface area was proposed for the electro-Fenton (E-Fenton) system. The GA was prepared by reduction self-assembly method. The physicochemical properties were characterized in details. The GA displayed a low electrochemical resistance and exhibited an excellent electrocatalytic activity. Comparing with the traditional carbon fiber and graphite felt cathodes, the GA cathode showed more positive oxygen reduction potential of 0.07 V (versus saturated calomel electrode). In E-Fenton system, H₂O₂ could be in situ electro-generated efficiently and continuously via a two-electron oxygen reduction reaction on the GA cathode. The electron transfer number n was calculated to be 1.0–2.0 for GA. The production of H₂O₂ of 107.6 mg L⁻¹ was obtained for GA in 90 min. Good performance was exhibited to degrade antibiotic ciprofloxacin. Results showed that nearly 100% ciprofloxacin degradation ratio and 91% TOC removal were achieved in 90 min and 120 min, respectively, which were much higher than control groups. The mineralization current efficiency was 12.75% in 30 min. It was attributed to the plenty of macro-pores of GA acted as reaction trap to accelerate electro-generated H₂O₂ decomposing by Fe²⁺ to form ·OH efficiently, which was verified by probe molecule trapping experiments and electron paramagnetic resonance analysis. Simultaneously, the strong charge transfer ability of GA was beneficial to the conversion of Fe³⁺/Fe²⁺. The GA also presented distinguished reusability and stability. Therefore, GA is a promising candidate material for E-Fenton cathode due to low cost, high efficient and corrosion resistance.

提出了一种新的具有高比表面积的大孔石墨烯气凝胶（GA）阴极，用于电子芬顿（E-Fenton）体系。GA通过还原自组装法制备。详细表征了其理化性质。GA表现出低的电化学电阻，并表现出优异的电催化活性。与传统的碳纤维和石墨毡阴极相比，GA阴极显示出更高的正氧还原电势，为0.07 V（相对于饱和甘汞电极）。在E-Fenton系统中，H ₂ O ₂可以通过GA阴极上的两电子氧还原反应高效连续地原位产生。对于GA，电子转移数n计算为1.0-2.0。H的产生90分钟内获得GA的₂ O ₂为107.6 mg L ^-1。表现出良好的降解抗生素环丙沙星的能力。结果表明，在90分钟和120分钟内，环丙沙星的降解率分别达到近100％，TOC去除率达到91％，远高于对照组。30分钟内矿化电流效率为12.75％。这归因于大量的GA大孔充当了反应陷阱，加速了Fe ²⁺分解产生的电生成的H ₂ O ₂。形成有效的·OH，并通过探针分子捕获实验和电子顺磁共振分析进行了验证。同时，GA的强电荷转移能力有利于Fe ³⁺ / Fe ²⁺的转化。GA还展示了出色的可重用性和稳定性。因此，由于低成本，高效率和耐腐蚀性，GA是用于电子芬顿阴极的有前途的候选材料。