Asymmetric supercapacitors based on carbon nanofibre and polypyrrole/nanocellulose composite electrodes

摘要: Asymmetric, all-organic supercapacitors (containing an aqueous electrolyte), exhibiting a capacitance of 25 F g−1 (or 2.3 cm−2) at current density 20 mA cm−2 and maximum cell voltage 1.6 V, are presented. The devices contain composite consisting polypyrrole covered Cladophora cellulose fibres (PPy–cellulose) as the positive electrode while carbon nanofibre material, obtained by heat treatment same PPy–cellulose under nitrogen gas flow, serves negative electrode. Scanning transmission electron microscopy combined with X-ray photoelectron spectroscopy data show that gives rise to porous topologically almost identical original composite. specific gravimetric capacitances electrodes were found be 59 146 g−1, respectively, asymmetric exhibited energy 33 J g−1. latter value is about two times higher than densities obtainable for symmetric device result larger range accessible. 156 was 11 cycling stability results further indicate capacity loss 23% during 1000 cycles employing cm−2. present represent significant step forward towards realization material based electrolytes commercially viable densities.