High temperature thermoelectric properties and energy transfer devices of Ca 3Co 4− xAg xO 9 and Ca 1− ySm yMnO 3

Abstract

The high temperature oxide thermoelectric materials of p-type Ca 3Co 4− x Ag x O 9 (denoted as p-Co349/Ag x ) and n-type Ca 1− y Sm y MnO 3 (denoted as n-Mn113/Sm y ) were prepared by the self-ignition method combined with a sintering technique. The influence of doping Ag and Sm on the thermoelectric properties of the corresponding materials was evaluated. The figures of merit, ZT, for the p-Co349/Ag 0.2 and n-Mn113/Sm 0.02 materials reached maxima of 0.20 and 0.15 at 973 K, respectively. The performances of thermoelectric devices constructed with the p- and n-type pairs were evaluated in terms of the maximum output power ( P max) and manufacturing factor. The P max and volume power density for the four-leg devices reached 36.8 mW and 81.9 mW cm −3 at Δ T of 523 K, respectively.