热处理条件对纳米锌铝尖晶石颗粒尺寸的影响  

Effect of Heat Treatment on Size of ZnAl_2O_4 Nano-particles

作　　者：文钰斌 刘新红[1] 陈晓雨[1] 杨林[1] 马腾[1] 

机构地区：[1]郑州大学河南省高温功能材料重点实验室,郑州450052

出　　处：《硅酸盐学报》2017年第6期880-886,共7页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金面上项目(51672253);河南省重点科技攻关项目(152102410014);河南省科技厅基础研究项目(162300410044)资助

摘　　要：以硝酸铝、硝酸锌和柠檬酸为原料,采用溶胶–凝胶法制备纳米锌铝尖晶石粉体,研究了热处理条件(温度和气氛)对纳米锌铝尖晶石颗粒尺寸的影响。结果表明:在空气气氛下,600℃热处理后即可制备出纳米锌铝尖晶石颗粒,纳米颗粒团聚严重,其颗粒尺寸在20~30 nm之间;随热处理温度升高,纳米锌铝尖晶石颗粒尺寸快速增加,1 000℃开始出现微米尺寸颗粒,1 400℃大部分颗粒尺寸在微米级别,且呈烧结状。在还原性气氛下,柠檬酸分解残留部分碳,碳分布在锌铝尖晶石颗粒间,可阻碍纳米锌铝尖晶石团聚和烧结,进而抑制高温下纳米锌铝尖晶石颗粒长大,1 000℃热处理后,纳米尖晶石颗粒尺寸较小(约10 nm)。然而,在还原性气氛下,当热处理温度≥1 200℃时,锌铝尖晶石与CO或柠檬酸分解残留的碳反应,使锌以气态的形式逸出,只有α-Al_2O_3晶相。ZnAl2O4 nano-powder was prepared by a sol-gel method with aluminum nitrate, zinc nitrate and citric acid as starting materials. Effect of heat treatment condition （i.e., temperature and atmosphere） on the size of ZnAl2O4 nano-particles was investigated The results show that ZnAlO4 nano-powder can be prepared in air at 600℃, and the nano-particles with the sizes of 20-30nm are seriously agglomerated. The size of ZnAl2O4 nano-particles increases greatly with increasing temperature, some micron-sized particles appear after heat treatment at 1 000 ℃, most of ZnAl2O4 nano-particles grow into micron-sized particles after they are sintered at 1 400 ℃. In a reductive atmosphere, there is residual carbon from citric acid decomposition. The carbon inclusions are well distributed in the boundaries of ZnAl2O4 particles, which can restrict the particle growth and/or lower the mobility of pores attached to particle boundaries, creating a retard effect on the growth and sintering behavior of ZnAl2O4 particles. The nano-particle size is approximately 10nm even after heat treatment at 1 000 ℃. However, in a reductive atmosphere, ZnAl2O4 reacts with CO or C （from citric acid decomposition） to form volatile Zn （g）, and there is only single crystal phase of α-Al2O3 when the temperature increases to 1 200 ℃.

关 键 词：溶胶-凝胶法 纳米锌铝尖晶石 气氛 纳米颗粒 

分 类 号：TB35[一般工业技术—材料科学与工程]