Hierarchical MnO2 Located on Carbon Nanotubes for Enhanced Electrochemical Performance

Shaohui Li; Lin Gao; Lichuan Wang; Mingkui Wang; Yan Shen

Index: 10.1002/celc.201701110

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Abstract

Abstract: Herein, we assembled an asymmetric supercapacitor (ASC) with high energy and power density based on porous MnO2/nitrogen‐doped carbon nanotubes (MnO2/NCNTs) in the positive electrode and chemical activated of nitrogen‐doped carbon nanotubes (ANCNTs) in the negative electrode. The ANCNTs//MnO2/NCNTs ASC device operates reversibly at a high voltage of 2.0 V in 1.0 M Na2SO4 and exhibits a high energy density of 37.2 Wh kg−1, which can be included in the top category of supercapacitors. More importantly, the supercapacitor exhibits impressive rate capability (high power density of 15100 W kg−1 at an energy density of 12.8 Wh kg−1) and exceptional cycling stability with 95.2 % capacitance retention after 3000 cycles. These attractive results indicate the potential for efficient energy storage devices.