Novel hybrid micro-supercapacitor based on conducting polymer coated silicon nanowires for electrochemical energy storage

The development of a novel hybrid symmetric micro-supercapacitor based on poly(3,4-ethylenedioxythiophene) coated silicon nanowires using an ionic liquid (N-methyl-N-propylpyrrolidinium bis(trifluoromethylsulfonyl)imide) as an electrolyte has been demonstrated. The hybrid supercapacitor device was able to deliver a specific energy of 10 W h kg-1 and a maximal power density of 85 kW kg-1 at a cell voltage of 1.5 V. The hybrid device exhibited long lifetime and an outstanding electrochemical stability retaining 80% of the initial capacitance after thousands of galvanostatic charge-discharge cycles at a high current density of 1 mA cm-2. The improvement of the capacitive properties compared with the bare SiNWs was attributed to the pseudo-capacitive behavior induced by the conducting polymer coating.The authors acknowledge the CEA for financial support of this work. This project has received funding from the European Union's Seventh Programme for research, technological development and demonstration under grant agreement no. 309143 (2012–2015).Peer Reviewe