Electrospun carbon nanofiber-carbon nanotubes coated polyaniline composites with improved electrochemical properties for supercapacitors

The carbon nanofiber-carbon nanotube (CNF-CNT) composites were fabricated by simple electrospinning and carbonization of polyacrylonitrile (PAN)-CNT solution prepared by first sonicating and stirring the CNT in N, N-dimethylformamide (DMF) as solvent. Aniline monomer was then coated on the composite materials via in situ chemical polymerization to form CNF-CNT-PANI composite. The as-prepared samples were then characterized. Importantly, the dispersed CNTs in the CNF-CNT composites were crucial for the CNF-CNTs acting as supports for the CNF-CNT-PANI composites to attain high electrochemical properties. The composite electrode material is found to be used as effective electrode material for supercapacitors with specific capacitance as high as 1119 F g−1 at 1 A g−1 compared to the bare CNF film with a specific capacitance of 278 F g−1. The composite electrode displaced excellent cyclic stability with retention of 98% even after 2000 cycles at a current density of 10 A g−1.