| Full text | |
| Author(s): |
Total Authors: 4
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| Affiliation: | [1] Univ Sao Paulo, Inst Quim, BR-05513970 Sao Paulo - Brazil
Total Affiliations: 1
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| Document type: | Journal article |
| Source: | Journal of the Brazilian Chemical Society; v. 25, n. 3, p. 460-U236, MAR 2014. |
| Web of Science Citations: | 6 |
| Abstract | |
In this work, the electrochemical behavior of Mg and Fe in ionic liquids (IL) were studied. We performed a series of cyclic voltammetry experiments to improve the understanding of Mg behavior in an IL containing the bis(trifluoromethanesulfonylimide) ([Tf2N]) anion. The results show an irreversible deposition/dissolution of Mg at a high water concentration (ca. 1300 ppm, 50 mmol L-1) and very low reversibility (7.3%) at a moderate water concentration (ca. 65 ppm, 5 mmol L-1). The formation of a film on the electrode surface and the presence of Mg were confirmed by scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDS). The process irreversibility indicates the formation of a passivating film. Because the presence of water affects the reversibility of the process, studies of Fe deposition/dissolution were conducted in two different ILs and with microelectrodes to evaluate how the water modifies the reversibility and the diffusion of ions. Water plays an important role in the reversibility of Fe deposition/dissolution being that deposition is less reversible when water is absent. The Fe diffusion is also modified because the Fe ion coordination sphere is strongly affected by the presence or absence of water; the Fe diffusion was also shown to depend on the coordination ability of the cation. (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: | 09/09209-4 - Metal electrodeposition in ionic liquids |
| Grantee: | Vitor Leite Martins |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |
| FAPESP's process: | 11/16078-3 - Graphene electrochemistry in ionic liquids |
| Grantee: | Lucas Lodovico de Carvalho |
| Support Opportunities: | Scholarships in Brazil - Master |