Direct Growth of Ultrathin NiCo2O4/NiO Nanosheets on SiC Nanowires as a Free-Standing Advanced Electrode for High-Performance Asymmetric Supercapacitors

Abstract

In this paper, we successfully employed SiC nanowires (SiC NWs) with splendid anticorrosion, antioxidation, heat-resistant properties, excellent conductivity, and large specific surface area directly deposited on carbon cloth (CC) as scaffolds to grow first the loose, porous and ultrathin NiCo2O4/NiO nanosheets (NiCo2O4/NiO NSs) via a facile hydrothermal technology coupled with annealing treatment to form a free-standing and stable hybrid electrode for asymmetric supercapacitor (ASC). Benefiting from the smart combination of SiC NWs and NiCo2O4/NiO NSs, illustrating a promising synergistic strategy, the electrode delivered an ultrahigh specific capacitance of 1801 F g–1 at 1 mA cm–2 as well as a remarkable rate capability of 1499 F g–1 at 10 mA cm–2. Furthermore, the additive-free functionalized SiC NWs@NiCo2O4/NiO NSs on CC acted as the positive electrode, assembled with the activated carbon (AC) on nickel foam (NF) negative electrode to fabricate an advanced ASC with intriguing electrochemical performan...