热处理条件对纳米锌铝尖晶石颗粒尺寸的影响

发布时间：2018-10-04 22:56

【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。
[Abstract]:Nanocrystalline zinc-aluminum spinel powders were prepared by sol-gel method using aluminum nitrate, zinc nitrate and citric acid as raw materials. The effects of heat treatment conditions (temperature and atmosphere) on the particle size of nanocrystalline zinc-aluminum spinel were studied. The results show that nanocrystalline zinc-aluminum spinel particles can be prepared after heat treatment at 600 鈩，

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