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采用共沉淀法并以氨水作为沉淀剂制备ZAO粉体,研究了pH值、煅烧温度对ZAO粉体形貌、尺寸和晶体结构的影响,并研究了粉体在无水乙醇中的分散工艺。借助差热-热重分析、X射线衍射、透射电子显微镜和紫外可见分光光度计对所制ZAO粉体进行表征。结果表明:ZAO前驱体的平均粒径随着滴定终点pH值的增大而减小,pH值小于8时,形貌不规则,pH值为9和10时,呈球形状,ZAO粉体的晶粒尺寸随着pH值增加先增大后减小,Al元素的掺杂使得ZnO的晶胞收缩;采用该法制备的ZAO前驱体中的阴离子难以洗净,煅烧温度在800℃以上时杂质才分解完全,ZAO粉体的晶粒尺寸随着煅烧温度的增加而增加;ZAO粉体在无水乙醇中最佳的分散工艺为添加ZAO粉体质量分数8%(质量分数)的六偏磷酸钠超声50min。
ZAO powder was prepared by co-precipitation method and ammonia as precipitant. The effects of pH and calcination temperature on the morphology, size and crystal structure of ZAO powder were studied. The dispersion of powder in ethanol was also studied. The ZAO powder was characterized by means of DTA - TG, XRD, TEM and UV - Vis spectrophotometer. The results showed that the average particle size of ZAO precursors decreased with the increasing of the titration end point pH. When the pH value was less than 8, the morphology was irregular. When the pH value was 9 and 10, The crystal size increases first and then decreases with the increase of pH value. The doping of Al element makes the unit cell of ZnO shrink. The anions in ZAO precursor prepared by the method are difficult to be washed. When the calcination temperature is above 800 ℃, Only completely decomposed, the grain size of ZAO powder increased with the increase of calcination temperature; the best dispersion technology of ZAO powder in absolute ethanol was the addition of hexametaphosphoric acid (by mass fraction) of ZAO powder Sodium ultrasound 50min.