Role of urea in the preparation of highly porous nanocomposite aerogels

被引:40
作者
Casula, Maria F.
Loche, Danilo
Marras, Sergio
Paschina, Giorgio
Corrias, Anna
机构
[1] Univ Cagliari, Dipartimento Sci Chim, I-09042 Cagliari, Italy
[2] Univ Cagliari, INSTM, I-09042 Cagliari, Italy
关键词
D O I
10.1021/la0635799
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
The preparation of highly porous CoFe2O4-SiO2 nanocomposite aerogels was successfully achieved by a novel sol-gel procedure involving urea-assisted co-gelation of the precursor phases. This method allows fast gelation, giving rise to an aerogel with 97% porosity. The formation of CoFe2O4 nanocrystals homogeneously distributed within the matrix occurs after calcination at 750 degrees C and is complete at 900 degrees C. Despite the high temperature required for the formation of the CoFe2O4 nanocrystals, the high porosity typical of aerogels is still retained.
引用
收藏
页码:3509 / 3512
页数:4
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