title: Control of excitation and quenching in multi-colour electrogenerated chemiluminescence systems through choice of co-reactant.
abstract: We demonstrate a new approach to manipulate the selective emission in mixed electrogenerated chemiluminescence (ECL) systems, where subtle changes in co-reactant properties are exploited to control the relative electron-transfer processes of excitation and quenching. Two closely related tertiary-amine co-reactants, tri-n-propylamine and N,N-diisopropylethylamine, generate remarkably different emission profiles: one provides distinct green and red ECL from [Ir(ppy)3] (ppy=2-phenylpyridinato-C2,N) and a [Ru(bpy)3](2+) (bpy=2,2'-bipyridine) derivative at different applied potentials, whereas the other generates both emissions simultaneously across a wide potential range. These phenomena can be rationalized through the relative exergonicities of electron-transfer quenching of the excited states, in conjunction with the change in concentration of the quenchers over the applied potential range.
authors.affiliation: Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Faculty of Science, Engineering and Built Environment, Deakin University, Geelong, Victoria 3216 (Australia).
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Barbante
authors.forename: Noah
authors.initials: N
authors.lastname: Kebede
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Hindson
authors.forename: Egan H
authors.initials: EH
authors.lastname: Doeven
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Zammit
authors.forename: Graeme R
authors.initials: GR
authors.lastname: Hanson
authors.forename: Conor F
authors.initials: CF
authors.lastname: Hogan
authors.forename: Paul S
authors.initials: PS
authors.lastname: Francis
mesh_terms: D015082:2,2'-Dipyridyl / Q000737:chemistry*; D003116:Color; D055664:Electrochemical Techniques; D005021:Ethylamines / Q000737:chemistry*; D007495:Iridium / Q000737:chemistry*; D049449:Luminescence; D008163:Luminescent Measurements; D011437:Propylamines / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*
chemical_list: D005021:Ethylamines; D011437:Propylamines; C096226:tripropylamine; D007495:Iridium; D015082:2,2'-Dipyridyl; C027070:N,N-diisopropylethylamine; D012428:Ruthenium
keywords: co-reactants; electrogenerated chemiluminescence; electron transfer; iridium; ruthenium