I am interested in this project as I already completed one major project on oxide ion conductors. I want to know the characterization techniques you used to research the new conductors. This conductor is oxide based or any other type?
if your sample is thin film, Hall measurement will be the best choice for measuring the Conductivity, mobility, Carrier concentration, type of conduction (p or n).
AC conductivity around 1 kHZ measurement is one of the best methods for finding the conductivity of the samples. You can extraplot to 0 frequency and determine the DC conductivity as well.
As mentioned already impudence spectroscopy. But I have also used the IV from the Keithley 4200 SCS for quick screening, the lakeshore HMS and the Hall effect measurement.