Authors: Ankam Bhaskar YC Huang ChiaJyi Liu
Publish Date: 2013/11/07
Volume: 25, Issue: 1, Pages: 249-254
Abstract
Polycrystalline samples of Ca3−xYbxCo395Ga005O9+δ x = 000 002 005 and 010 have been prepared by conventional solidstate synthesis The XRD results revealed that all the samples are single phase The thermopower of all the samples was positive indicating that the predominant carriers are holes over the entire temperature range The electrical resistivity thermopower increased and total thermal conductivity decreased with increasing Yb3+ content Ca295Yb005Co395Ga005O9+δ had the highest dimensionless figure of merit of 0035 at 300 K which is about 346 higher than that of the undoped sample These results suggested that the partial substitution of Yb3+ ion improves the thermoelectric properties of Ca3Co4O9+δ
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