Hierarchical nickel cobaltite nanoneedle arrays armored flexible electrospinning carbon nanofibers membrane for electrochemical deionization

Crafting an ideal capacitive deionization (CDI) cathode presents a significant challenge, owing to the myriad requisites it must fulfill. These entail a high specific capacitance, commendable conductivity, stability, and the counteraction of the shortcomings inherent in additive/binder electrodes. Realizing all these attributes from a single-component material, however, is a daunting task. In this investigation, we present our findings on the in-situ cultivation of ultrathin NiCo2O4 nanoneedle arrays on freestanding electrospinning nitrogen-enriched carbon nanofibers devised to tackle these hurdles. The resultant material boasts remarkable features that not only alleviate tension triggered by phase transition but also accentuate electric conductivity. Electrochemical evaluations authenticate the effectiveness of structural modulation, reflected through a markedly augmented specific capacitance, superior stability, and diminished electrochemical resistance. Furthermore, the assembled pliable, asymmetric CDI cell incorporating electrospinning carbon nanofiber showcases superior desalination capabilities (38.86 mg g−1 at 1.2 V), a swift desalination rate (0.65 mg g−1 min−1), and improved cycle stability. This work finding contribute valuable interpretations towards proficiently designing and developing advanced CDI electrode materials capable of meeting the stringent requisites for high specific capacitance, good conductivity, and stability. It further propels progress towards industrialization, thereby expediting the realization of practical applications.