Modification strategy of carbon-based electrode for vanadium redox flow batteries

Vanadium redox flow battery (VRFB), as a novel energy storage battery in the field of electrochemical energy storage, exhibit advantages such as stable performance, high energy storage capacity, and excellent safety, making them highly promising for large-scale energy storage applications. Among the key components of VRFB, electrodes play a decisive role in determining the overall battery performance. Carbon-based electrodes offer good conductivity, corrosion resistance and low cost, but their low catalytic activity and poor hydrophilicity hinder the electrochemical performance of VRFB, so addressing these issues has become an urgent priority. This paper summarizes four common modification strategies for carbon-based electrodes, including: metal and metal oxide modifications, surface structural defect engineering, activation through oxygen-containing functional groups, and heteroatom doping engineering. The first and second strategies involve the introduction of an external catalyst, while the third and fourth strategies focus on the intrinsic modification of the carbon-based material itself. These strategies aim to fundamentally address the inherent limitations of carbon-based materials, enhance their electrochemical catalytic activity, and improve the electrochemical performance of VRFB. Finally, the paper discusses the future prospects of electrode development, hoping to provide valuable insights for the advancement of VRFB technology.