Al_2O_3掺杂ZnO纳米粉体的制备及气敏特性研究

Preparation and Gas Sensing Property Studies of Al_2O_3-doped ZnO Nanopowder

采用sol-gel法制备了w（Al2O3）为2%-4%的Al2O3-ZnO纳米粉体,利用XRD和SEM等测试手段分析了粉体的微观结构。研究了Zn2＋浓度、pH值和清洗对粉体制备的影响。采用静态配气法测试了由所制粉体制成的气敏元件对丙酮、乙醇、甲醇等气体的气敏性能。结果表明：用该法得到的粉体材料颗粒粒径小,工作温度为160℃时,由w（Al2O3）为3%的粉体在700℃退火制得的气敏元件对体积分数为40%的丙酮的灵敏度最高可达到7 779,响应-恢复时间均为1s.

Al2O3-doped ZnO nanopowders containing 2%～4% Al2O3 were prepared by the sol-gel method,and their microstructure was characterized by XRD and SEM.Powders preparation was investigated towards Zn2＋ concentration,pH and cleaning.Gas sensors were fabricated from the prepared nanopowders,and the sensitivity of them to acetone,ethanol and methanol was measured via the static volumetric method.The results indicate that the particle size of obtained nanopowders is small.For sensors fabricated from nanopowders containing 3% Al2O3 under the annealing temperature of 700 ℃,the maximum sensitivity to acetone（volume fraction：40%） reaches 7 779 at the operating temperature of 162 ℃.The response-recovery time is 1 s.