中文摘要：

利用溶胶凝胶方法、高压成型结合无压烧结方法制备了Y掺杂的Ca3Co4O9热电材料（YxCa3-x Co4O9,x=0.2）,考察了成型压力对样品微结构及高温电学性能的影响.测试结果表明：高压能够提高Ca3Co4O9样品致密度和织构度,大幅降低其电阻率;随着温度的升高,样品的电阻率降低,Seebeck系数增大.在1 000 K的温度下,3 GPa高压条件成型制得的Y0.2Ca2.9Co4O9样品具有最高的功率因子（P=3.83μW/cm·K2）,约为常规压力成型后烧结样品的2.3倍.

英文摘要：

Thermoelectric materials Ca3Co409 doped with Y in the composition of Y0.2 Ca2.8 Co4O9 were prepared by sol-gel method combined high - pressure compacting technique followed by pressureless sintering. The microstructures of the oxides were investigated and the electrical properties （including of Seebeck coeffi- cient and electrical conductivity） were measured from room temperature to 1000 K. It was found that high pressure compacting helps to improve the density and texture of Ca3 Co4O9. The electrical resistivity decreases with an increase of temperature, while the Seebeck coefficient increases with an increase of temperature. The maximum power factor 3.9 μW/cmK2 at 973K is obtained for the sample pressed by high pressure