High-energy asymmetric supercapacitor based on petal-shaped MnO2 nanosheet and carbon nanotube-embedded polyacrylonitrile-based carbon nanofiber working at 2 V in aqueous neutral electrolyte

• Published in: Journal of power sources Vol. 249; pp. 1 - 8
• Main Authors: WANG, Chen-Hao, HSU, Hsin-Cheng, HU, Jin-Hao
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier 01.03.2014
• Subjects: Applied sciences; Asymmetry; Capacitance; Capacitors; Capacitors. Resistors. Filters; Carbon; Carbon fibers; Electrical engineering. Electrical power engineering; Electrodes; Energy density; Exact sciences and technology; Nanostructure; Various equipment and components; Nanosheet; Nanoparticle; Manganese dioxides; Carbon nanotubes; Nanostructure; Electrolytic capacitor; Aqueous electrolyte; Nanostructures; Asymmetric supercapacitors; Nanoparticles; Acrylonitrile polymer; High energy; Electrochemistry; Supercapacitor; Manganese Oxides; Aqueous solution; Carbon fiber
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2013.10.068

An asymmetric supercapacitor (ASC) uses very thin petal-shaped MnO2 nanosheets as the positive electrode and a network of carbon nanotube-embedded polyacrylonitrile-based carbon nanofibers (CNT-CNF electrodes) as the negative electrode. It has a high specific capacitance and a high specific energy density in 0.5 M Na2SO4. An assembled MnO2//CNT-CNF ASC is operated reversibly at a high cell voltage of 2.0 V and exhibits a high specific capacitance of 93.99 F g-1 and an excellent energy density of 52.22 Wh kg-1, which is better than those of ASCs that are based on MnO2//carbon, which can be found in the literature. The MnO2//CNT-CNF ASC has superior cycling stability with 92% retention of initial specific capacitance after 2000 cycles.