Journal
PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
Volume 468, Issue 2137, Pages 18-34Publisher
ROYAL SOC
DOI: 10.1098/rspa.2011.0323
Keywords
pH; pure water; double-layer; biosensor
Categories
Funding
- Australian Research Council
Ask authors/readers for more resources
Water maintains a pH value of 7 owing to a balance between dissociation into hydronium (H(3)O(+)) and hydroxide (OH(-)) ions and their recombination. An examination is made of the effect of applying voltages from 0.1 to 0.82V on these ions between metal electrodes which act as blocking electrodes. The movement of hydronium ions away from and hydroxide ions towards the anode is followed. This movement results in the formation of an ion double-layer with a steeply rising electric field and a maximum pH of approximately 12. At the cathode, the opposite occurs and the pH reaches a minimum of approximately 1.7. The time constant for double-layer formation is found to increase exponentially with voltage, and the pH at each electrode varies linearly with voltage; thus, the pH can be controlled systematically at each electrode. The dimensions of the double-layers are such that large biomolecules at the electrodes will be immersed in a pH environment close to the extreme values at the electrode. This means that the charge on the molecules may be controlled as they adsorb onto the electrode; this may prove valuable for the operation of biosensors.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available