热电氧化物(Ca_3Co_2O_6)_(1-x)(Ca_3Co_4O_9)_x的制备和表征

Preparation and Marking Series of Thermoelectric Oxides (Ca_3Co_2O_6)_x(Ca_3Co_4O_9)_(1-x)

热电氧化物Ca3Co2O6和Ca3Co4O9是Ca-Co-O体系中两个确定的态,其热电性质显著不同.我们采用“快速加热法”制备了(Ca3Co2O6)1-x(Ca3Co4O9)x(x=0,0.2,0.4,0.6,0.8,1),并利用XRD、SEM等实验方法分析表征样品,系统研究了热电氧化物从Ca3Co2O6到Ca3Co4O9的转化过程.从SEM图中可知Ca3Co2O6为无规取向棒状结构,Ca3Co4O9为法向取向与表面近似垂直的片状结构,XRD结果显示x=0.4之前的样品Ca3Co2O6和Ca3Co4O9两相衍射峰并存,x=0.6以后的样品是Ca3Co4O9单相.

In Ca-Co-O system, there are two identified phases Ca_3Co_2O_6 and Ca_3Co_4O_9 with much different thermoelectric properties. We have prepared (Ca_3Co_2O_6)_x(Ca_3Co_4O_9)_ 1-x(x=0,0.2,0.4,0.6,0.8,1) by “rapid heating procedure” and investigated series of samples using XRD,SEM techniques. From SEM figure we can see that Ca_3Co_2O_6 has short-bar structure with all kinds of directions and Ca_3Co_4O_9 has flaky structure which is parallel to the surface. The result of XRD showed us that the samples before x=0.6 exist both materials peaks, the samples after x=0.6 only exist Ca_3Co_4O_9 one material's XRD peak.