TY - JOUR
T1 - Characterisation of biphasic electrodes based on the liquid N,N-didodecyl-N'N'-diethylphenylenediamine redox system immobilised on porous hydrophobic silicates and immersed in aqueous media
AU - Shul, Galyna
AU - McKenzie, Katy J.
AU - Niedziolka, Joanna
AU - Rozniecka, Ewa
AU - Palys, Barbara
AU - Marken, Frank
AU - Hayman, Colin M.
AU - Buckley, Benjamin R.
AU - Bulman Page, Philip C.
AU - Opallo, Marcin
PY - 2005
Y1 - 2005
N2 - Biphasic electrodes based on the water-insoluble redox liquid N,N-didodecyl-N,N'-diethylphenylene-diamine (DDPD) neat and dissolved in di-(2-ethyl-hexyl)phosphate (HDOP) deposited onto silicate matrices were prepared and studied in aqueous electrolyte media. As electrode substrates (i) bare gold, (ii) a gold surface covered with a hydrophobic silicate film, and (iii) a hydrophobic silicate carbon composite were employed. Both hydrophobic silicate based materials act as a host for the organic redox liquid and modify the electrochemical response in characteristic manner. The electrooxidation of DDPD occurs at the organic phase\aqueous phaselelectrode triple phase boundary and is accompanied by the transfer of the anion from the water into the organic phase. In the presence of an organic acid, HDOP, the oxidation process is accompanied by the expulsion of protons instead. This electrochemically driven proton exchange process results in a shift of redox potentials, which can be described by Nernst-type dependence with a slope strongly dependent on the electrode/host material and the deposition method. The formation of an DDPD-HDOP acid-base complex within microdroplets deposited deposited on gold surfaces is confirmed by IR reflectance spectra. (C) 2005 Elsevier B.V. All rights reserved.
AB - Biphasic electrodes based on the water-insoluble redox liquid N,N-didodecyl-N,N'-diethylphenylene-diamine (DDPD) neat and dissolved in di-(2-ethyl-hexyl)phosphate (HDOP) deposited onto silicate matrices were prepared and studied in aqueous electrolyte media. As electrode substrates (i) bare gold, (ii) a gold surface covered with a hydrophobic silicate film, and (iii) a hydrophobic silicate carbon composite were employed. Both hydrophobic silicate based materials act as a host for the organic redox liquid and modify the electrochemical response in characteristic manner. The electrooxidation of DDPD occurs at the organic phase\aqueous phaselelectrode triple phase boundary and is accompanied by the transfer of the anion from the water into the organic phase. In the presence of an organic acid, HDOP, the oxidation process is accompanied by the expulsion of protons instead. This electrochemically driven proton exchange process results in a shift of redox potentials, which can be described by Nernst-type dependence with a slope strongly dependent on the electrode/host material and the deposition method. The formation of an DDPD-HDOP acid-base complex within microdroplets deposited deposited on gold surfaces is confirmed by IR reflectance spectra. (C) 2005 Elsevier B.V. All rights reserved.
U2 - 10.1016/j.jelechem.2004.12.041
DO - 10.1016/j.jelechem.2004.12.041
M3 - Article
VL - 582
SP - 202
EP - 208
JO - Journal of Electroanalytical Chemistry
JF - Journal of Electroanalytical Chemistry
SN - 0022-0728
IS - 1-2
ER -