3.13 Examples of Ionic Conduction
3.13.1 Cobalt oxide and Nickel oxide: p-type Conductors
These are easily oxidizable oxides and are prone to metal vacancies (M1-xO) which govern the conduction.
The carrier concentration can be expressed as (hint: write the defect reaction, refer to the Defect Chemistry module)
In these materials, hole mobility is much larger than ionic mobility such that conductivity is essentially electronic. While Hall measurements can be used to measure the mobility, further conductivity measurements can yield the carrier concentration in these materials.
|
