Application of bio-based electrodes in emerging capacitive deionization technology for desalination and wastewater treatment

Capacitive deionization (CDI) is an emerging, efficient, cheap, and environmentally friendly water desalination technology. One of the most critical components of the CDI system is the electrodes; thus, improving their performance will promote its commercial application. The cost, efficiency, and availability of the electrode materials are the main challenges facing the application of the CDI in water desalination and wastewater treatment compared to other technologies. To reduce the cost of the electrodes, carbon materials derived from biomass and general wastes are being considered. A detailed review of the application of bio-based derived electrodes in CDI desalination and wastewater treatment is presented. A comparison between these novel materials and conventional carbon nanomaterials is discussed in terms of resource availability, ease of manufacture, cost, material specifications, and performance. Finally, future research recommendations are introduced to enhance this technology’s feasibility and performance.