中文摘要：

以硝酸铜、硝酸铁、硝酸钴和柠檬酸为原料,采用溶胶-凝胶自蔓延燃烧法一步直接合成了单相Co0.5Cu0.5Fe2O4纳米晶。借助TG/DTAI、R、XRD和SEM等手段分别对溶胶-凝胶自蔓延燃烧机理、粉体在不同退火温度下的结构演化过程以及燃烧粉体的表面形貌进行了研究。结果表明,自蔓延燃烧过程是在硝酸根离子和羧酸根离子之间进行的热诱导阴离子氧化还原反应,其中,硝酸根离子作氧化剂,羧酸根离子作还原剂。干凝胶燃烧后,产物已经初步晶化,晶粒尺寸约20nm。经600℃,2h退火即可得到晶化较好的Co0.5Cu0.5Fe2O4纳米粉体,燃烧粉末为多孔结构,密度为2.9g/cm3。

英文摘要：

The sol-gel self-propagating combustion method was used to prepare single phase nanocrystamne Co2.5 Cu2.5Fe2O4 ferrite from cupric nitrate, cobalt nitrate, ferric nitrate and citrate. The sol-gel self-propagating combustion mechanism, the phase evolution of the xerogel, as-burnt powder and samples annealed at different temperature, as well as the surface morphology of as-burnt powder were studied by TG/DTA, IR, XRD and SEM. The results revealed that the self-propagating combustion process was a heat-induced anion redox reaction between nitrate ions and carboxyl group wherein nitrate ions acted as oxidant and carboxyl group as reductant. The as-burnt powder had been of primary crystal with crystalline size about 20nm and a well-crystallized Co2.5 Cu2.5Fe2O4 ferrite could be obtained after being annealed at 600℃ for 2h. The as-burnt powder was porous mi- crostructure and the corresponding density was 2.9g/cm^3.