Na_(1.4)Co_2O_4基热电材料的溶胶-凝胶法制备及表征  

PREPARATION OF Na_(1.4)Co_2O_4 BASED THERMOELECTRIC MATERIALS BY SOL-GEL METHOD AND CHARACTERIZATION

作　　者：厉英[1] 马北越[1] 王臻明[1] 姜茂发[1] 

机构地区：[1]东北大学材料与冶金学院,沈阳110819

出　　处：《金属学报》2011年第1期109-114,共6页Acta Metallurgica Sinica

基　　金：国家自然科学基金项目51074038和50774018资助~~

摘　　要：采用溶胶-凝胶法制备了掺杂Sr,Li和Cu的Na_(1.4)Co_2O_4基热电材料,采用XRD分析了Na_(1.4)Co_2O_4基热电材料的相组成.通过DTA-TG曲线确定材料的预烧结和终烧结温度分别为450和850℃.研究了掺杂量对Na_(1.4)Co_2O_4基材料电阻率、Seebeck系数和功率因子等热电性能的影响.结果表明,掺杂Li可降低Na_(1.4)Co_2O_4的电阻率,掺杂Sr和Cu使材料的电阻率增加;掺杂Li和Cu可大幅度提高Na_(1.4)Co_2O_4的Seebeck系数和功率因子;掺杂Sr的改善效果不显著,掺杂Li的效果最好;当Li掺杂量为0.40,Na_(1.4)Co_2O_4基热电材料的功率因子在15℃时达到最大值7444.73μW.m^(-1).K^(-2).Sr, Li and Cu-doped Na1.4Co2O4 based thermoelectric materials were prepared by sol-gel process. The phase constitution of Na1.4Co2O4 based thermoelectric materials was analyzed by XRD. According to DTA-TG curves, the pre-sintering and sintering temperatures of the materials were obtained to be 450℃and 850℃, respectively. The influences of doping amount on the electrical resistivity, Seebeck coefficient and power factor of Na1.4Co2O4 based materials were investigated. The results showed that doping Li could decrease the electrical resistivity of Na1.4Co2O4 doping Sr and Cu could increase the electrical resistivity. Doping Li and Cu could improve the Seebeck coefficient and power factor of Na1.4Co2O4. The improving effect on Na1.4Co2O4 by doping Sr is not remarkable but by doping Li is the best. When 0.40 Li was doped, the power factor of Na_（1.0）Li_（0.4）Co_2O_4 at 15℃reaches maximum value of 7444.73μW·m^-1.K^-2.

关 键 词：热电材料 钴酸盐 热电性能 掺杂 溶胶-凝胶法 

分 类 号：TB34[一般工业技术—材料科学与工程]