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采用柠檬酸络合-微波法合成La0.8Sr0.2CoO3粉体,研究微波条件下的制备工艺。XRD表明,微波合成20min和25min时得到的粉体其XRD图谱的衍射峰与标准La0.8Sr0.2CoO3的特征峰(peaks)一致,晶相单一。SEM图表明微波焙烧20min合成的La0.8Sr0.2CoO3粉体团聚现象明显减弱,粒径分布也变得均匀,尺寸较小,几乎都在纳米级;而焙烧25min得到的粉体变成一大块,形成致密的一个表面,不适合作为催化剂使用。通过粒度及比表面积分析可知,微波合成法比普通电炉合成法得到的La0.8Sr0.2CoO33粉体具有更大比表面积,因此可以为气固相的催化反应提供更大的比表面积,从而大大提高催化效率。
Synthesis of La0.8Sr0.2CoO3 powders by citric acid complexation - microwave method and their preparation under microwave condition were studied. The results of XRD show that the diffraction peaks of the XRD patterns of the powders obtained at 20 min and 25 min after microwave synthesis are consistent with the peaks of the standard La0.8Sr0.2CoO3 with a single crystalline phase. The SEM images show that the aggregation of La0.8Sr0.2CoO3 powders after microwave baking for 20min is obviously weakened, the particle size distribution becomes uniform and the size is small, almost all in the nanometer scale; and the powder obtained after baking for 25min becomes a large piece , The formation of a dense surface, not suitable as a catalyst. Through the analysis of particle size and specific surface area, we can see that La0.8Sr0.2CoO33 powder obtained by microwave synthesis method has a larger specific surface area than that of La0.8Sr0.2CoO33 powder obtained by the synthesis method of ordinary electric furnace, so it can provide larger specific surface area for the catalytic reaction of gas-solid phase and greatly increase Catalytic efficiency.