• CNT-based electrodes offer high specific surface area, superior electrical conductivity, and excellent electrochemical stability, making them promising for capacitive deionization.
• Material engineering and structural design strategies significantly enhance the salt electrosorption capacity and cycling stability of CNT-based CDI electrodes.
• CDI provides a cost-effective and environmentally friendly alternative to conventional desalination methods, operating at low voltages without chemical additives.
• Future research should focus on overcoming challenges such as electrode fouling and scalability to realize the full potential of CNT-based CDI technology.