胶囊状ZnO的水热合成及其丙酮气敏特性研究

Hydrothermal synthesis of capsule-like ZnO and its gas sensing properties to acetone

以Zn（CH3COO）2·2H2O和NaOH为原料,十六烷基三甲基溴化铵（CTAB）为表面活性剂,经水热过程合成了胶囊状ZnO粉体,利用X射线衍射仪（XRD）及扫描电镜（SEM）对产物的物相和微观形貌进行了表征,并用静态配气法测试了其厚膜型元件的气敏性能。结果表明：所得ZnO具有六方相纤锌矿结构,平均直径约500 nm,长度约1-2μm,分散性良好,其厚膜型元件在工作温度为290℃时对体积分数为100×10–6的丙酮气体具有快速的响应能力和良好的选择性,且灵敏度达到33。

Capsule-like ZnO powders were synthesized through a hydrothermal process with Zn（CH3COO）2 · 2H2O and NaOH as raw materials, and cetyl trimethyl ammonium bromide （CTAB） as surfactant. The phase composition and microstructure of the products were characterized by X-ray diffraction （XRD） and scanning electron microscope （SEM）. The thick film-type sensor based on the products was prepared and it＇s gas sensitive properties were evaluated with stationary state gas distribution method. The results indicate that the products possess hexagonal wurtzite structure and good dispersity with an average diameter of 500 nm and a length of 1-2 μm. At the working temperature of 290 ℃, the thick film-type sensor based on the capsule-like ZnO powders shows rapid response and excellent selectivity to acetone （volume fraction of 100× 10-6）, and the sensitivity reaches 33.