Defects
In the most stable fluorite phase of ceria, it exhibits several defects depending on partial pressure of oxygen. The primary defects of concern are oxygen vacancies and small polarons (electrons localized on cerium cations) because these two are located in the "useful" range of ceria. In the case of oxygen defects, the increased diffusion rate of oxygen in the lattice causes increased catalytic activity as well as an increase in ionic conductivity, making ceria interesting as a fuel cell electrolyte in solid-oxide fuel cells.
Read more about this topic: Cerium(IV) Oxide
Famous quotes containing the word defects:
“We often make use of envenomed praise, that reveals on the rebound, as it were, defects in those praised which we dare not expose any other way.”
—François, Duc De La Rochefoucauld (1613–1680)
“The machine is impersonal, it takes the pride away from a piece of work, the individual merits and defects that go along with all work that is not done by a machine—which is to say, its little bit of humanity.”
—Friedrich Nietzsche (1844–1900)
“One of our defects as a nation is a tendency to use what have been called “weasel words.” When a weasel sucks eggs the meat is sucked out of the egg. If you use a “weasel word” after another there is nothing left of the other.”
—Theodore Roosevelt (1858–1919)