Thermoelectric Properties of Y1−x Ag x BaCo4O7+δ Ceramics

Abstract

The thermoelectric properties of the Ag-doped ceramics Y1−x Ag x BaCo4O7+δ (x = 0.0, 0.05, 0.1, 0.15, and 0.2) were investigated from 373 K to 973 K. The results show that the doping of Ag can reduce the electrical resistivity. The Seebeck coefficients of the samples decrease when the Ag doping amount is small, but increase when the Ag doping amount is large. The activation energy of the electrical conductivity was calculated using Arrhenius plots, and it was found that the activation energy descends with increase of the Ag doping amount. According to the power factors, the optimum Ag doping amount is x = 0.15, which results in a higher power factor of 81 μW m−1 K−2 at 973 K, 72.7% higher than for the sample without Ag doping.