【摘要】 采用真空熔融缓冷方法制备了单相β-Zn4Sb3以及含有过量Zn的β-Zn4Sb3块体热电材料.在300—700K的温度范围内测试了材料的电导率、Seebeck系数和热导率,研究了β-Zn4Sb3化合物中过量Zn的分布状态及其对材料热电性能的影响规律.结果表明:过量的Zn作为第二相较均匀的分布在β-Zn4Sb3的晶界上,随着Zn含量增加,材料电导率和热导率上升,Seebeck系数下降,Zn第二相的引入能有效提高材料的功率因子,Zn过量2at%的材料在700K时其ZT值达到1·10.更多还原

【Abstract】 Single-phase β-Zn₄Sb₃ bulk sample and several samples based on β-Zn₄Sb₃ with different amounts of Zn were produced by melting in an evacuated quartz ampoule followed by slow cooling and their thermoelectric properties were investigated at 300 to 700K.The distribution of Zn in the samples was observed and the effects of excess of Zn on thermoelectric properties of β-Zn₄Sb₃ compound were investigated systematically. With the amount of Zn increasing, electrical and thermal conductivities of the sample increase, and the Seebeck coefficient declines. The excess of Zn leads to an obvious improvement to the power factor of the β-Zn₄Sb₃ based materials. The ZT max of the sample is 1.10 at 700K when the amount of excessive Zn is 2at%.更多还原