N-doped porous carbon-based capacitive deionization electrode materials loaded with activated carbon fiber for water desalination applications

Capacitive deionization (CDI) is a kind of emerging desalination technology. The development of electrode materials with a high desalination rate and long life, which can be used in seawater/brine water desalination and the reduction of salty wastewater, is a research hotspot in the aspect of global water treatment. In this study, N-doped porous carbon was combined with activated carbon fibers by a green coating method to successfully prepared CDI electrode (NPC@ACF). The microstructure and electrode performance of NPC@ACF were characterized by different techniques. The specific surface area of NPC@ACF tested by BET was 1098 m2 g−1. The electrochemical performance of this material was studied, showing that the NPC@ACF electrode possesses a high specific capacitance of 268.90 F g−1. At the voltage of 1.2 V, the electrosorption capacity is 14.63 mg g−1, and the CDI desalination efficiency was increased by 39% and 63% compared with that of pure ACF or NPC, respectively. The NPC@ACF material has good recyclability showing a desalination efficiency retention rate of 27% after 50 cycles. With its recyclability, stability, and enhanced electrochemical characteristics, the NPC@ACF electrode has been proved to be an excellent electrode for CDI applications.