Manganese oxide doping carbon aerogels prepared with MnO2 coordinated by N, N - dimethylmethanamide for supercapacitors

Abstract

Carbon aerogels with excellent conductive characteristics and high specific capacitance have attracted more and more interests for next-generation energy storage applications. Three-dimensional interconnected Mn2O3/carbon aerogel supercapacitor electrodes are prepared by a novel doping method using MnO2 coordinated by N, N-dimethylmethanamide (DMF). The coordinative MnO2 (DMF/MnO2) plays a key role in the sol-gel process of resorcinol and formaldehyde. The doped carbon aerogels exhibits a high specific surface area of 859 m2 g−1 and a good pore-size distribution of 10–15 nm. All of the doped carbon aerogels exhibit higher specific capacitance than pure carbon aerogels, and the highest specific capacitance (170 F g−1), at current density of 1.0 A g−1, is obtained in Mn–CA–5% when 5 mol% DMF/MnO2 is added to the precursor solution. The specific capacitance is as high as 100 F g−1, at current density of 10.0 A g−1, and 97% of initial capacitance is retained over 1000 cycles at a current density of 5.0 A g−1. The doped carbon aerogels exhibits a high coulombic efficiency (up to 99.8%) and a good rate capability. The corresponding result is due to the novel doping method of DMF/MnO2 addition.