LI Jiashu, HU Zhiqiang, HAO Hongshun, QIN Yiying, LI Yawei
(School of Textile and Materials Engineering, Dalian Polytechnic University, Dalian 116034, Liaoning, China)
Abstract: Ca3Co4O9 thermoelectric material doped with Na/Cu were prepared by the sol-gel method. The samples were characterized by XRD, SEM and porosity measurement. The effects of Na/Cu dosage on the resistivity, Seebeck coefficient and power factor of samples were explored. The results showed that the XRD patterns of double-doped samples were consistent with the standard JCPDS pattern, and no impurities were found. The density of the double doped samples was improved, and their resistivity was greatly reduced. With the temperature increasing, the resistivity decreased, Seebeck coefficient and the power factor increased, and the thermoelectric performance improved; at 1050 K, the power factor of the (Na0.1Ca0.9)3(Co0.9Cu0.1)4O9 sample reached 448 μW/mK2.
Key words: Na-Cu double doped; Ca3Co4O9; thermoelectric material; resistivity; Seebeck coefficient