Modified carbon electrodes as multifunctional platforms for next-generation water and wastewater treatment

Modified carbon electrodes are emerging as a cornerstone in advancing sustainable water and wastewater treatment technologies, addressing the escalating complexity of contaminants and inherent limitations of conventional methods. This review synthesises recent developments in electrode modification strategies and their application across three key electrochemical platforms: capacitive deionisation, microbial fuel cells and electro-Fenton processes. Enhanced pore structures in capacitive deionisation facilitate efficient electrosorption and selective ion removal; biocompatible, conductive surfaces in microbial fuel cells promote microbial adhesion and electron transfer, fostering improved bioelectricity generation; while catalytically active carbons in electro-Fenton systems enable robust in-situ hydrogen peroxide production for advanced pollutant degradation. Collectively, these tailored carbon materials demonstrate increased system performance, cost reduction, and accelerated adoption of sustainable water treatment and energy recovery approaches. This review further delineates key challenges in scaling laboratory innovations to practical large-scale systems, while underscoring the pivotal, versatile role of modified carbonaceous electrodes in advancing sustainable water decontamination, energy recovery and overall treatment efficacy.