Frontiers of carbon materials as capacitive deionization electrodes

Capacitive deionization (CDI), which is based on ion electrosorption on the surface of electrically charged electrodes, has attracted widespread attention as a novel, cost-effective and environment-friendly desalination technology. Carbon materials are widely used as CDI electrodes due to their high specific surface area (SSA), superior conductivity, and better stability. Many research efforts have been made to further enhance the CDI performance of carbon materials. In this review, the performance-enhancing strategies of various carbon materials including activated carbon, porous carbon, carbon aerogels, carbon nanotubes and graphene are systematically presented. We also explain the significance of the development of CDI technology and identify where further work is urgently required and where challenges are still faced.