Carbon Dioxide Sensing Systems Based On Processes At Triple Phase Boundary Interfaces
|Norahim Ibrahim 1,2, Frank Marken 1|
1. University of Bath, Department of Chemistry, Claverton Down, Bath BA2-7AY, United Kingdom
In this study, we developed a novel way to detect CO2 based on ion transfer processes at a triple phase junction graphite|4-(3-phenylpropyl)pyridine|aqueous electrolyte. Cobalt phthalocyanine (CoPc) readily dissolved in the organic 4-(3-phenylpropyl)pyridine phase and exhibited oxidation/reduction processes which are coupled to liquid|liquid ion transfer. In order to maintain charge neutrality, each one-electron oxidation (reduction) process is coupled to the expulsion (insertion) of cations (here Li+, Na+, K+, Ca2+ and Mg2+). The introduction of CO2 into the triple phase boundary system resulted in different potential shifts for all cation types studied. The range of cations studied allowed effects of cation sizes and CO2 binding to the organic phase to be explored.
Figure. 1 Cyclic voltammogram at 0.05 V s-1 for the oxidation/reduction of 80 nL deposit of a solution of CoPc (84 mM) in 4-(3-phenylpropyl)pyridine, immobilized onto a 4.9 mm diameter basal plane pyrolytic graphite electrode, and immersed in 0.1 M NaClO4, in the absence and presence of carbon dioxide.
|Auxiliary resources (full texts, presentations, posters, etc.)|
Presentation: Short communication at SMCBS'2009 International Workshop, by Norahim Ibrahim
See On-line Journal of SMCBS'2009 International Workshop
Submitted: 2009-08-31 13:36 Revised: 2009-09-04 13:23