Thermoelectric properties of delafossite-type layered oxides Agln1-xSnxO2 -: art. no. 013706

The thermoelectric properties of delafossite-type layered oxides AgIn1-xSnxO2 that consist of alternating layers of Ag and In1-xSnxO2 were investigated to elucidate their potential as a thermoelectric material. Polycrystalline materials of the AgIn1-xSnxO2 were prepared by a cation exchange reaction between NaIn1-xSnxO2 and AgCl. The solubility limit of the Sn atoms on the In sites was approximately x=0.05. The electrical conductivity and Seebeck coefficient were measured between 373 and 673 K in air. Undoped AgInO2 was an n-type semiconductor with conductivities of 10(-4)-10(-2) Omega(-1) cm(-1), and the electron carriers were generated via the formation of oxygen vacancies. AgIn0.95Sn0.05O2 was an n-type degenerate semiconductor with conductivities of 10(0)-10(1) Omega(-1) cm(-1) where the Sn atoms acted as electron donors. This drastic increase in the electrical conductivity increased the thermoelectric power factor by approximately two orders of magnitude to 10(-6)-10(-5) W m(-1) K-2. (c) 2005 American Institute of Physics.