Akademik Veri Yönetim Sistemi
JOURNAL OF ELECTRONIC MATERIALS, cilt.51, sa.9, ss.5159-5168, 2022 (SCI-Expanded)
Free-standing carbon nanofibers are crucial electrode materials for supercapacitors. Herein, nanocube-embedded porous carbon nanofibers (P-CNFs) from manganese(II) chloride/cobalt(II) chloride/iron(III) nitrate-polyacrylonitrile (Mn/Co/Fe@ PAN) were fabricated using electrospinning followed by a thermal treatment. The self-formation of uniformly distributed nanocubes over the carbon nanofiber was confirmed by scanning electron microscopy (SEM). P-CNF//P-CNF-based supercapacitors (SCs) using flexible and free-standing electrodes without any binder demonstrated a high mass specific capacitance of 107.4 F g(-1) at 1 A g(-1) and a good specific energy of 3.68 Wh kg(-1) in 1 M H2SO4 electrolyte. Even at a high specific power, 2000 W kg(-1), it retained a high specific energy of 3.18 Wh kg(-1) Moreover, the supercapacitor cell exhibited a remarkable rate capability with a retention of 85.5% froml to 8 A g(-1) and it possessed a prominent cycle stability of 97.9% after 50,000 cycles, which are really significant values reported in the literature for CNF-based electrodes to date. The high electrochemical cyclability and stability of P-CNFs originated from a combination of hierarchical porous structure of nanofibers with decoration of metallic nanoparticles. This unique nanocube structure provided more electrochemically active sites which are conductive towards electrochemical reactions. The reaction kinetics were also studied and the percentage of capacitive- and diffusion-controlled capacitance were found as 88% and 12%, respectively. As a result, addition of ternary metallic salts plays a significant role in improving ultrastable energy storage systems.