通过溶胶凝胶-自蔓延燃烧法制备了纳米尖晶石CuFe2O4材料,采用TG-DTA、XRD、FTIR、N2-吸附脱附、SEM等技术对样品进行表征,探究溶胶凝胶-自蔓延燃烧法的机理及焙烧温度对尖晶石CuFe2O4材料晶体结构的影响.结果表明,前体溶胶中金属离子与柠檬酸—COOH形成三维网状的柠檬酸络合物,使金属离子分散于溶胶体系中;200～230℃时柠檬酸络合干凝胶自蔓延燃烧,大量络合物发生原位分解,放出大量的热,生成正式CuFe2O4尖晶石晶型,并有明显正四面体和正八面体亚晶格出现,晶粒尺寸约25.6nm;经400℃焙烧后,不完全燃烧形成的碳残留物分解,同时正式CuFe2O4尖晶石晶型发生转变,形成片状的Fe[CuFe]O4反式尖晶石晶型;随着焙烧温度升高,晶格尺寸从13.9nm增长到58.2nm,反式尖晶石晶型结晶程度逐渐增强,片状结构逐渐融合,形成层状整体,比表面积逐渐减小.%The spinel CuFe2O4 were prepared by sol-gel auto-combustion method. The mechanism of the preparation method and the effect of the calcination temperature on the structure of the CuFe2O4 spinel crystal,were investigated by characterizing the samples with TG-DTA,XRD,FTIR,N2-adsorption desorption and SEM. It was found that the metal ions were evenly dispersed in the precursor sol system, when the citric acid complex compound was formed. The auto-combustion occurred at 200—230℃,and the citric acid complex compound decomposed by releasing lots of heat. The CuFe2O4 formal spinel crystal with tetrahedron and octahedron sublattice was formed and the grain size was about 25.6nm. The carbon residue formed by incomplete combustion was decomposed,when calcinated at 400℃. The CuFe2O4 formal spinel crystal transformed to lamellar trans-spinel crystal Fe[CuFe]O4 at the same time. As the rising of the calcination temperature,the size of the lattice group increased from 13.9nm to 58.2nm,and the lamellar trans-spinel crystal gradually merged to entirety.
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