Electrochemical Capacitances of a Nanowire-Structured MnO2 in Polyacrylate-Based Gel Electrolytes

Abstract

Nanowire-structured MnO2 was synthesized by a sonochemical method and its electrochemical capacitances were investigated in three kinds of electrolytes: liquid-type KCl solution, potassium polyacrylate (PAAK), and potassium polyacrylate-co-polyacrylamide (PAAK-PAAM) gel polymer electrolytes (GPEs). The prepared MnO2 with a nanowire structure had a high specific surface area and narrow pore distribution, which was very useful for gel-type electrolyte in supercapacitor applications. The specific capacitance of nanowire-structured MnO2 with PAAK electrolyte exceeded 484 F g(-1) at the conventional loading weight of MnO2 (1.02 mg cm(-2)) in the electrode. The nanowire-structured MnO2 with PAAK electrolytes was a very promising electrode material for high-performance supercapacitors. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.112206jes] All rights reserved.