Co3O4掺杂SnO2体系的乙醇和丙酮气敏特性

通过研磨、涂浆和700 ℃ 烧结3 h的方法， 得到了一系列Co3O4掺杂的SnO2纳米颗粒厚膜． 发现在300 ℃ 的工作温度下复合膜对乙醇和丙酮表现了很好的气敏性质， 尤其是在摩尔比Co/Sn为5%时效果达到最好． 对1000 ppm的乙醇和丙酮的灵敏度分别为301和200，为没有Co掺杂时的SnO2时的7倍和5倍．同时，Co3O4的掺杂没有使得对H2的灵敏度有很大的提高，即提高了乙醇和丙酮对氢气的选择性．最后讨论了提高气敏性能的机制．

Gas Sensing Properties of Co3O4-loaded SnO2 to Ethanol and Acetone

A series of Co3O4-loaded SnO2 nanocomposite thick films were prepared by grinding, screen-printing and sintering at 700 ±C for 3 h. XRD data showed the nanocomposite thick films were rutile structure of SnO2 and cubic Co3O4. The composite films were found to exhibit good response to alcohol and acetone at 300 ±C. The film went through a sharp sensitivity maximum at 5 mol%CoO4=3 with a change in Co3O4 content. At 300 ±C, the maximum sensor response to alcohol and acetone, each 1000 ppm in air, was 301 and 235, respectively, which was about 7 and 5 times as large as that of the pure SnO2 respectively. The selectivity to alcohol and acetone over H2 and CO also was promoted by the addition of Co3O4 to SnO2. The mechanism of such strong promotion of sensor response (electronic sensitization) is discussed.