High performance of symmetric micro supercapacitors based on silicon nanowires using N-methyl-N-propylpyrrolidinium bis(trifluoromethylsulfonyl)imide as electrolyte

David Aradilla (1, 2) , P. Gentile (1) , Gérard Bidan (3) , Vanesa Ruiz (4) , Pedro Gómez-Romero (4) , Thomas J.S. Schubert , Hülya Sahin , Elzbieta Frackowiak (5) , Saïd Sadki (2)

1 SiNaps - Silicon Nanoelectronics Photonics and Structures
2 SPRAM - UMR 5819 - Structures et propriétés d'architectures moléculaire
3 INAC - Institut Nanosciences et Cryogénie
4 ICN2 - ICN2 - Institut Catala de Nanociencia i Nanotecnologia
5 Faculty of Chemical Technology

This work describes the development and performance of a symmetric microsupercapacitor made of nanostructured electrodes based on silicon nanowires (SiNWs) deposited using chemical vapor deposition (CVD) on silicon substrates. The performance of the SiNWs micro-supercapacitor employing an aprotic ionic liquid (N-methyl-N-propylpyrrolidinium bis(trifluoromethylsulfonyl)imide) (PYR13TFSI) as an electrolyte was able to deliver a maximal power density of 182 mW cm-2 and a specific energy of 190 µJ cm-2 operating at a wide cell voltage of 4V with a quasi-ideal capacitive behaviour. The lifetime of the device exhibited a remarkable electrochemical stability retaining 75 % of the initial capacitance after several million galvanostatic charge-discharge cycles at a high current density of 1 mA cm-2. Furthermore, a coulombic efficiency of approximately 99 % was obtained after galvanostatic cycling test without structural degradation on the morphology of SiNWs.

Mots clés: Silicon nanowires; micro-supercapacitors; ionic liquids; electrochemical energy storage; chemical vapor deposition

Domaines: Energie électrique; Matériaux

David Aradilla, P. Gentile, Gérard Bidan, Vanesa Ruiz, Pedro Gómez-Romero, et al.. High performance of symmetric micro supercapacitors based on silicon nanowires using N-methyl-N-propylpyrrolidinium bis(trifluoromethylsulfonyl)imide as electrolyte. 2014. ⟨cea-01053082⟩