【摘要】 以Co(NO3)2·6H2O,Ca(NO3)2·4H2O为原料,Na2CO3为沉淀剂,采用化学共沉淀法和放电等离子烧结(SPS)制备了Ca2Co2O5化合物。采用TG-DTA、XRD和SEM等手段对前驱体的热分解过程,样品的物相以及形貌进行了表征,测试了Ca2Co2O5的热电性能。实验结果表明:沉淀前驱物经850oC预烧8h后,利用SPS850oC,压力30MPa保温5min,制备了纯相Ca2Co2O5化合物。该化合物的电阻率和热导率均随温度的升高而降低,800oC时,热电性能优值(ZT)为0.12。更多还原

【Abstract】 Ca2Co2O5 compound was prepared by coprecipitation method and spark plasma sintering (SPS). Co(NO3)2· 4H2O and Ca(NO3)2· 6H2O were used as raw materials and Na2CO3 was used as precipitation agent. The pyrolytic decomposition mechanism of the precursor, phase and the morphology of the sample were investigated by TG-DTA, XRD and SEM. The thermoelectric properties of Ca2Co2O5 compound were investigated. The results show that the Ca2Co2O5 compound can be obtained by using the powders calcined at 850oC for 8h after spark plasma sintering at 850oC and 30 MPa for 5min. The electric resistivity and thermal conductivity decrease with temperature increasing within the measured temperature range. The ZT value is estimated to be 0.12 at 800oC.更多还原