Polyaniline decorated salt activated phenolic resin/PAN-based carbon nanofibers with remarkable cycle stability for energy storage applications

•The PANI decorated activated carbon nanofibers (PANI/CNF-A) were prepared.•The symmetric supercapacitor device was fabricated using PANI/CNF-A.•The fabricated device showed a good energy density of 13.3 Wh kg−1.•The device showed a remarkable cyclic stability of nearly 100% after 5,000 cycles. Polyaniline (PANI) decorated salt-activated phenolic resin (PR)/polyacrylonitrile (PAN)-based carbon nanofibers (PANI/CNFs) were fabricated by the consecutive solution electrospinning, salt activation and PANI electrodeposition methods for supercapacitor applications. The electrochemical energy storage properties of the PANI-decorated activated PANI/CNFs (activated PAN: CNF-A, activated PR/PAN28 (weight ratio of PR and PAN is 2:8): CNF28-A) were evaluated by assembling the electrodes into a symmetric supercapacitor (SSC) device. The specific capacitance of the device was ca. 336F g−1 at the current density of 1 A/g. The device possessed an energy density of 13.33 Wh kg−1 at a power density of 200 W kg−1 with a retention life of nearly 100 % after 5,000 cycles.