Electrical behaviour of lanthanum- and cobalt-doped strontium stannate

Electrical properties of lanthanum- and cobalt-doped strontium stannate, SrSnO3, have been studied as a function of temperature. All the compositions investigated have cubic structure. Measurement of Seebeck coefficient in one of the cobalt-doped SrSnO3 sample shows that it exhibitsp-type conductivity. Results of AC conductivity measurements show that conduction occurs by hopping of charge carriers in lanthanum-doped samples and forx=0·01 in cobalt-doped sample. Inx=0·05 sample in cobalt-doped system, conduction seems to occur in extended states.