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利用溶胶-凝胶法制备亚锰酸盐化合物La_(0.65)Sr_(0.35)MNO_3,通过XRD和SEM研究不同pH值对合成粉体相组成和微观形貌的影响.结果发现:在pH值为0.5的酸性环境和pH为8.0的弱碱性环境中,均可以获得具有钙钛矿结构且尺寸均匀的La_(0.65)Sr_(0.35)MNO_3粉体.在pH值为0.5的酸性环境中,有利于形成二维层状结构的凝胶,而在pH为8.0的弱碱性环境中,有利于形成三维空间网络结构的凝胶,金属离子可以有效地分散于这两种凝胶中,避免了后期热处理过程中化学组分的偏差及团聚的生成.

La_(0.65)Sr_(0.35)MNO_3 was prepared at different pH values by sol-gel method. The phase composition of the as-received powder was measured using X-ray diffraction. The particle size and morphology were observed by SEM. The results show that the samples called manganites have single perovskite structure and homogeneous particle size distribution when the pH value is controlled near 0.5 and 8.0 during the sol-gel process. The layer-shaped gel forms in the system when pH=0.5. However, the three-dimensional reticulate gel occurs when pH=8.0. The homogeneous distribution of La, Sr and Mn ions in the gel benefits avoiding the deviation of the chemical composition of manganites and the agglomeration of the powder in the following heat treatment.

参考文献

[1] Russek S L;Zimm C .[J].International Journal of Refrigeration-Revue Internationale du Froid,2006,29:1366.
[2] 郑文君,庞文琴.新型复合钙钛矿 Ba(Sb Ⅲ,Sb Ⅴ)O3的水热合成和表征[J].无机材料学报,2000(02):275-280.
[3] Yu B F;Gao Q;Zhang B et al.[J].International Journal of Refrigeration-Revue Internationale du Froid,2003,26:622.
[4] Manh-Huong Phan;Seong-Cho Yu .[J].Journal of Magnetism and Magnetic Materials,2007,308:325.
[5] 钟喜春,曾德长,刘正义,魏兴钊.室温磁致冷材料及技术的研究进展[J].材料科学与工程学报,2003(02):302-306.
[6] Dixit A;Majumder S B;Dobal P S.[J].Thin Solid Films,2004(56):284.
[7] 张明福,赫晓东,韩杰才,杜善义.自燃烧法合成 BaNd2Ti5O14的凝胶化及热处理研究[J].无机材料学报,2000(05):879-883.
[8] 赵九蓬,李垚,强亮生,王彪,张贺新.有机凝胶法低温合成纳米SrxBa1-xNb2O6粉体[J].无机材料学报,2004(01):75-80.
[9] 李凤华,王珏,刘常升,樊占国.柠檬酸溶胶-凝胶法合成YBa2Cu3O7-δ[J].东北大学学报(自然科学版),2003(11):1061-1063.
[10] 沈彩,刘庆峰,刘茜.柠檬酸-硝酸盐燃烧法制备Ba0.5Sr0.5TiO3介电材料[J].无机材料学报,2004(03):681-685.
[11] 魏楸桐,郭瑞松,李海龙,王凤华.溶胶凝胶-燃烧法合成La0.7Sr0.3MnO3阴极材料及其性能[J].电源技术,2005(05):286-288,306.
[12] 丁子上;翁文剑;杨娟 .[J].硅酸盐学报,1995,23(05):571.
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