It is Proposed to fabricate a thermoelectric generator with P - N structure by sintering the N - type CaMnO3 together with the P - type Ca3 Co4 O9 directly. It is necessary to sinter CaMnO3 ceramic below the phase transition temperature of Ca3 Co4 O9 , 926 癈. In this paper, CaMnO3 powder wsa synthesized using the solid reaction method, then mixed with Bi2O3 and pressed into pellet. Sintering was carried out in air at 900cC for 12h. The microstructure and thermoelectric properties of prepared sample were also investigated. As a result, there was no detectable secondary phase caused by additional Bi2O3; the average electrical conductivity increased and the approximate Seebeck coefficient decreased with increasing adding of Bi2 O3; the average electrical conductivity and the approximate Seebeck coefficient increased with increasing temperature. The addition of Bi2O3 promoted the sintering process and decreased the sintering temperature, and effectively improved the thermoelectric properties of CaMnO3 sample as well.%采用固相反应法制备CaMnO3粉末,加入Bi2O3混合、压块后,在900℃烧结12h得到样品,并对样品的物相、组织和热电性能进行了测试分析.结果表明:制备出的热电材料是单相的CaMnO3,加入Bi2O3后没有形成可观测的第二相；随着Bi2O3加入量的增加,样品的平均电导率增大,温差电势减小；平均电导率随温度的增加而增加,呈半导体特性,温差电势随温度的增加而增大；加入Bi2O3促进了烧结,降低了烧结温度,改善了材料的热电性能.
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