A review of carbon-based electrocatalytic electrodes for reducing anionic pollutants in wastewater

Abstract

Electrochemical processes are emerging as viable alternatives for enhancing conventional wastewater treatment technologies. This paper explores the use of carbon-based electrodes, such as carbon nanotubes (CNTs) and graphene, in decontaminating anionic pollutants from wastewater. Carbon-based electrodes, including various graphene derivatives, exhibit high efficiency in degrading and mineralizing recalcitrant organic pollutants like cyanide, fluoride, nitrate, nitrite, phosphate, sulfate, and chloride. Introducing pulsed voltage applications allows for in-situ electrochemical cleaning of electrode materials, boosting performance despite higher energy consumption. The stability and application of these electrodes present challenges that must be addressed for practical implementation. The paper summarizes the key conclusions from current investigations and examines the decontamination efficacy of several carbon-based electrodes concerning various anionic contaminants. Important factors impacting their practical application include environmental issues, current efficiency, electrode durability, and corrosion resistance. The review also emphasizes the effectiveness of carbon and graphene derivatives in treating wastewater containing anionic contaminants, especially in removing anionic dyes. These materials possess excellent electrochemical and adsorption properties, making them highly efficient in eliminating pollutants. Research has shown that graphene-based materials, due to their large surface area and high conductivity, significantly enhance the decontamination process. Carbon-based electrodes, particularly those derived from graphene, have considerable potential to improve wastewater treatment efficiency. They are a valuable addition to current water filtration methods by providing a sustainable and effective means to remove anionic contaminants.