File(s) under permanent embargo
Electrochemistry of tris(2,2′-bipyridyl) cobalt(II) in ionic liquids and aprotic molecular solvents on glassy carbon and platinum electrodes
journal contribution
posted on 2015-10-20, 00:00 authored by D Cabral, Patrick HowlettPatrick Howlett, Jenny PringleJenny Pringle, X Zhang, D MacFarlaneThe tris(2,2′-bipyridyl) complexes of cobalt(II) and (III) ([Co(bpy)3]2+/3+) produce a redox couple of great interest in thermoelectrochemical cells and dye sensitized solar cells including both types of devices based on ionic liquid electrolytes. We present a systematic study of the electrochemistry of [Co(bpy)3]2+ [NTf2]-2 in two ionic liquids (ILs) based on the 1-ethyl-3-methylimidazolium (C2mim) cation and two ILs based on the 1-butyl-1-methylpyrrolidinium cation (C4mpyr), as well as three aprotic molecular solvents. Platinum (Pt) and glassy carbon (GC) working electrodes were compared. In all solvents better electrochemical responses were observed on GC, which yielded higher currents in the cyclic voltammograms and lower rate constants for the redox reaction. The [Co(bpy)3]1+/2+ couple is also readily observed, but this redox reaction is chemically irreversible, possibly because the [Co(bpy)3]1+ complex dissociates. However, the [Co(bpy)3]1+/2+ reaction is chemically reversible in all of the solvents studied, except 3-methoxypropionitrile, if excess of 2,2′-bipyridyl is added to the solution.
History
Journal
Electrochimica actaVolume
180Pagination
419 - 426Publisher
ElsevierLocation
Amsterdam, The NetherlandsPublisher DOI
ISSN
0013-4686Language
engPublication classification
C Journal article; C1 Refereed article in a scholarly journalCopyright notice
2015, ElsevierUsage metrics
Categories
No categories selectedKeywords
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC