Improving the electrochemical activity of electrodes is essential to the development of vanadium redox flow battery (VRFB). In this work, we prepared a novel electrode with the modification of nitrogen-doped carboxyl multiwalled carbon nanotubes using dopamine as an eco-friendly nitrogen source (carboxyl [email protected]). Characterization and electrochemical measurements reveal that the synthesized carboxyl [email protected] graphite felt electrode (carboxyl [email protected]/GF) exhibits excellent electrochemical performance toward VO²⁺/$\text{V}{\text{O}}_2^{+}$ reaction. Superior battery performance was obtained with the energy efficiency of 80.54% at a current density of 80 mA cm⁻². Excellent durability of the carboxyl [email protected]/GF electrode was confirmed by long-term charge/discharge tests. The enhanced reaction kinetics of VO²⁺/$\text{V}{\text{O}}_2^{+}$ is ascribed to the synergetic effect of oxygen and nitrogen containing groups on graphite felt surface and the presence of nitrogen-doped carboxyl multiwalled carbon nanotubes (MWCNT). The facile approach proposed in this paper provides a new route to the fabrication of electrode with excellent performance for VRFB.

改善电极的电化学活性对于钒氧化还原液流电池（VRFB）的开发至关重要。在这项工作中，我们制备了一种新型电极，该电极使用多巴胺作为生态友好的氮源（羧基[受电子邮件保护]），对氮掺杂的羧基多壁碳纳米管进行了改性。表征和电化学测量表明，合成的羧基[受电子邮件保护的]石墨毡电极（羧基[受电子邮件保护的] / GF）表现出优异的对VO ²⁺ /的电化学性能。$\text{V}{\text{Ø}}_2^{+}$反应。在80mA cm ^-2的电流密度下以80.54％的能量效率获得了优异的电池性能。长期充电/放电测试证实了羧基[受电子邮件保护] / GF电极具有出色的耐久性。VO ²⁺ /的增强反应动力学$\text{V}{\text{Ø}}_2^{+}$这归因于石墨毡表面上含氧和氮的基团的协同作用以及氮掺杂的羧基多壁碳纳米管（MWCNT）的存在。本文提出的简便方法为VRFB的优异性能提供了一条新的电极制造途径。