摘要
应用ＴＧ、ＤＴＡ、ＩＲ、ＸＲＤ和ＣＯ２－ＴＰＤ等技术对用。ｃｅｌｌｕｌｏｓｅ吸附法合成Ｌａ０．８Ｓｒ０．２ＣｏＯ3（ＬＳＣＯ）粉体的过程机理进行了研究．发现在制备过程中ｃｅｌｌｕｌｏｓｅ首先起着一种金属离子吸附剂的作用．在焙烧的前期阶段，ｃｅｌｌｕｌｏｓｅ先被部分氧化而在其骨架上出现了羧酸基团，并与金属离子发生螫合形成螯合离子．优化条件下，在低温合成了纯相ＬＳＣＯ粉体．然而若焙烧过程中产生的ＣＯ２不能及时地排出，会导致体相中碳酸盐的形成,从而需要高于８００℃的再焙烧才能获得纯相的ＬＳＣＯ粉体．
The whole process of preparing La_0.8Sr_0.2CoO_3 oxide powders by a cellulose adsorp-tion method was investigated by TG, DTA, XRD, and CO_2-TPD techniques. It was found thatcellulose first acted as an adsorbent. During the initial stage of pyrolysis, the cellulose was partiallyoxidized, and some carboxyl groups were formed in the cellulose texture, which was then complexedwith the metal ions. At optimized condition, pure phase LSCO powder could be acquired at lowtemperature. But, if the produced CO_2 could not elute in time, carbonate would form duringpyrolysis, and a calcined temperature higher than 800℃ was needed.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2000年第1期124-130,共7页
Journal of Inorganic Materials
基金
九五攀登计划预选项目!95-予-36
国家自然科学基金!59789201
国家科委863计划!715-006-0122
关键词
吸附法
氧化物粉体
钙钛矿型
cellulose
synthesis
La_0.8Sr_0.2CoO_3
mechanism study
