Nitrogen/manganese oxides doped porous carbons derived from sodium butyl naphthalene sulfonate

Abstract

High-performance porous carbons have been prepared as supercapacitor electrode materials by co-doped with nitrogen and MnOx via a direct carbonization method, using sodium butyl naphthalene sulfonate (abbr. BNS–Na) as carbon source. It is believed that the in situ formed Na6(SO4)2(CO3) in the product would probably serve as temporary template for producing porous structures. The impacts of nitrogen/MnOx contents as well as the structures upon the capacitive performances were emphatically discussed. It indicates that introducing nitrogen and/or MnOx into the carbon matrix can remarkably improve their capacitive performances based on the cyclic voltammetry and galvanostatic charge–discharge measurements in 6molL−1 KOH aqueous solution. The specific capacitances of doped carbons can reach up to ca. 167.0–241.8Fg−1 compared with that of the undoped carbon of ca. 105.6Fg−1. Of these samples, the carbon–Mn-1:30-N-1:15 sample co-doped with nitrogen and MnOx exhibits the highest specific capacitance and energy density up to 241.8Fg−1 and 33.6Whkg−1, respectively. In particular, these carbons also exhibit high intrinsic capacitances (i.e., capacitance per surface area) up to ca. 0.66–1.92Fm−2.