Choice of Platinum
The choice of platinum for the hydrogen electrode is due to several factors:
- inertness of platinum (it does not corrode).
- the capability of platinum to catalyze the reaction of proton reduction
- a high intrinsic exchange current density for proton reduction on platinum
- excellent reproducibility of the potential (bias of less than 10 μV when two well-made hydrogen electrodes are compared with one another)
The surface of platinum is platinized (i.e., covered with platinum black) to:
- Increase total surface area. This improves reaction kinetics and maximum possible current
- Use a surface material that adsorbs hydrogen well at its interface. This also improves reaction kinetics
Other metals can be used for building electrodes with a similar function such as the palladium-hydrogen electrode.
Read more about this topic: Standard Hydrogen Electrode
Famous quotes containing the words choice of, choice and/or platinum:
“The question of place and climate is most closely related to the question of nutrition. Nobody is free to live everywhere; and whoever has to solve great problems that challenge all his strength actually has a very restricted choice in this matter. The influence of climate on our metabolism, its retardation, its acceleration, goes so far that a mistaken choice of place and climate can not only estrange a man from his task but can actually keep it from him: he never gets to see it.”
—Friedrich Nietzsche (1844–1900)
“Once women begin to question the inevitability of their subordination and to reject the conventions formerly associated with it, they can no longer retreat to the safety of those conventions. The woman who rejects the stereotype of feminine weakness and dependence can no longer find much comfort in the cliché that all men are beasts. She has no choice except to believe, on the contrary, that men are human beings, and she finds it hard to forgive them when they act like animals.”
—Christopher Lasch (b. 1932)
“Flouncing your skirts, you blueness of joy, you flirt of
politeness,
You leap, you intelligence, essence of wheelness with silvery nose,
And your platinum clocks of excitement stir like the hairs of a
fern.”
—Karl Shapiro (b. 1913)