Chemically modified graphite felt as an efficient cathode in electro-Fenton for p-nitrophenol degradation

• Published in: Electrochimica acta 2014-09, Vol.140, p.376-383
• Main Authors: Zhou, Lei, Zhou, Minghua, Hu, Zhongxin, Bi, Zhaoheng, Serrano, K. Groenen
• Format: Article
• Language: English
• Subjects: Chemical and Process Engineering; Chemical engineering; Chemical modification; Chemical Sciences; Electro-Fenton; Engineering Sciences; Graphite felt cathode; Hydrazine hydrate; p-Nitrophenol degradation
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2014.04.090

•Chemically modified graphite felt was prepared using ethanol and hydrazine hydrate as reagents.•Carbon nanoparticles with functional groups were deposited on the surface after modification.•The electrochemical activity for ORR and H2O2 generation on the modified electrode was improved.•The cathode modification effictively improved the EF performance for pollutant degradation. A simple method with low-cost chemical reagents ethanol and hydrazine hydrate was used to modify graphite felt as the cathode for electro-Fenton (EF) application, using p-nitrophenol (p-Np) as the model pollutant. Characterized by scanning electron microscope, contact angle, Raman spectrum and X-ray photoelectron spectroscopy, the morphology and surface physicochemical properties after modification were observed considerably changed. After modification, some nanoparticles and oxygen and nitrogen-containing functional groups appeared on the cathode surface, which greatly improved the surface hydrophilic property and the electrocatalytic activity for oxygen reduction reaction. The effects led to the hydrogen peroxide accumulation on the modified cathode markedly increased to 175.8mgL−1, while that on the unmodified one was only 67.5mgL−1. p-Np of initial 50mgL−1 could be completely removed by EF using the modified cathode, and the mineralization ratio reached 51.4%, more than 2 times of the pristine one. After 10 cycles, the mineralization ratio of the modified cathode was still above 45%, suggesting that the modification method can provide an effective approach to improve EF performance, and thus benefits to promote its environmental applications.