| Full text | |
| Author(s): |
Benedetti, Tania M.
[1]
;
Goncales, Vinicius R.
[1]
;
Cordoba de Torresi, Susana I.
[1]
;
Torresi, Roberto M.
[1]
Total Authors: 4
|
| Affiliation: | [1] Univ Sao Paulo, Inst Quim, BR-05513970 Sao Paulo - Brazil
Total Affiliations: 1
|
| Document type: | Journal article |
| Source: | Journal of Power Sources; v. 239, p. 1-8, OCT 1 2013. |
| Web of Science Citations: | 9 |
| Abstract | |
Macroporous manganese oxide films were produced via template-assisted electrodeposition methodology employing polystyrene spheres with different diameters as template, thereby producing films with different pore sizes. The obtained films were true casts of the template(s) employed, as evidenced by Field Emission Scanning Electron Microscopy. The influence of pore size on capacitive behavior was assessed by cyclic voltammetry experiments in conventional propylene carbonate/LiClO4. Besides the influence of pore size, four different ionic liquids (ILs) were studied as electrolytes, showing that the physico chemical nature of IL strongly affects the capacitive behavior of macroporous manganese oxide films, particularly in terms of stability throughout successive charge/discharge cycles. Optimal performance was obtained using 1-butyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)imide ({[}BMMI]{[}Tf2N]), in which a constant increase in capacitance was observed for the first 700 charge/discharge cycles. This capacitance remained constant, at least until the 1,000 cycle, and was higher than the capacitance achieved using conventional organic solvents. Moreover, the electrochemical window obtained using {[}BMMI]{[}Tf2N] was widened (from 0.9 V to 1.5 V), corresponding to a significant gain (up to 75%) in terms of energy density. Thus, the development of electrochemical capacitors may significantly benefit from macroporous manganese oxide film electrochemistry employing ionic liquids as electrolytes. (C) 2013 Elsevier B.V. All rights reserved. (AU) | |
| FAPESP's process: | 09/53199-3 - Molecular recognition and energy storage: fundamental studies concerning geometry, size and synthesis effects on the optimization of the chemical properties of electroactive materials |
| Grantee: | Roberto Manuel Torresi |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 12/02117-0 - Poly(ionic liquids) in electrochemical devices: polyelectrolytes for energy storage and conversion devices and stabilization of graphene and poly(3,4-etylenedioxidethiophene) (PEDOT) for electroactive films obtention |
| Grantee: | Tania Machado Benedetti |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 08/57805-2 - Institute of Bioanalytics |
| Grantee: | Lauro Tatsuo Kubota |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 11/15159-0 - Third generation biosensors based on the interaction among reduced graphene oxide, ionic liquids and oxidase enzymes. |
| Grantee: | Vinicius Romero Gonçales |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |