The thermoelectric properties of the samples greatly depend on the doping elements and constituent concentration . the sample with la - dopant shows better thermoelectric performances than those with other three dopants . it should be pointed out that there exists an appropriate range of doping values to improve the thermoelectric properties of the samples 这四种掺杂剂都不同程度的提高了材料的热电性能，但只有掺la能够很好的改善材料的性能，而且掺杂量不是越大越好，而是表现出有一个最优掺杂的限度。
