气敏材料An-WO_3催化特性的物理解释  

Physical explanation on the catalytic properties of Au-WO_3 gas sensing materials

作　　者：王旭升[1] 薛丽君[1] 周晓华[1] 三浦则雄[2] 山添升[2] 

机构地区：[1]西安电子科技大学技术物理学院,陕西西安710071 [2]日本九州大学研究生院材料科学与工程系

出　　处：《功能材料》2001年第3期287-289,共3页Journal of Functional Materials

摘　　要：对Ａｕ－ＷＯ３粉体材料的制备及氨敏特性进行了研究，得到材料的电阻和对氨的灵敏度随 Ａｕ含量的增加先增大，达到某一极值后减小的实验结果，本文还用透射电子显微镜（ＴＥＭ）观察了Ａｕ颗粒在ＷＯ３表面的分布情况，发现Ａｕ颗粒的团聚现象。根据电子催化模型时Ａｕ在ＷＯ３表面的随机分布情况进行了计算机模拟，模拟结果与实验观测现象相符，在此基础上给出了Ａｕ 颗粒催化机理的定性物理解释。Gas sensing materials WO3+xwt%Au were prepared by mixing WO3 with aqueous dispersions of respective colloidal Au particles. Their sensing properties to NH3 were measured in the conventional flow apparatus. It was observed that with increasing the concentration of Au loaded (wt%) the materials' resistance and NH3 sensitivity increased firstly and decrease after reaching the maximum. The TEM morphologies of Au-WO3 powders were characterized, and the reunion of Au grains were observed. In addition, the distribution of Au grains on the WO3 surface were simulated. The result of simulation and the phenomena observed agree with each other. According to this the physical explanation about the catalytic activity of Au was proposed.

关 键 词：半导体气体传感器 气敏机理 催化剂 气敏材料 

分 类 号：TN304.92[电子电信—物理电子学]