High-temperature thermoelectric properties of non-stoichiometric Ag1 − xInTe2 with chalcopyrite structure

Our group has revealed that AgGaTe2 with the chalcopyrite structure exhibits relatively high thermoelectric (TE) figure of merit (ZT) when it has a deviation of Ag content from the stoichiometry. The maximum ZT value of 0.77 was obtained for Ag0.95GaTe2 at 850 K. On the other hand, the TE properties of AgInTe2 with the same chalcopyrite structure with AgGaTe2 have not been investigated. In the present study, we examined the high-temperature TE properties of AgInTe2 with the composition of Ag1 − xInTe2 (x = 0, 0.01, 0.03, and 0.05). The deviation of Ag content from stoichiometry slightly enhanced the ZT value. The maximum ZT value was 0.07 at 600 K obtained in the samples of x = 0.03 and 0.05.