多孔ZnO微米球的制备及其优异的丙酮敏感特性

摘要

以六水合硝酸锌、尿素为原料,以六亚甲基四胺为表面活性剂,利用水热法合成了多孔氧化锌微米球.通过X射线衍射仪、扫描电子显微镜和吸附仪对样品的结构、形貌、比表面积和孔径进行了表征.利用所得多孔微米球氧化锌制备了气敏元件,并对其气敏特性进行了测试.结果表明：在280◦C的工作温度下,表面多孔氧化锌微米球气敏元件对50 ppm的丙酮气体的灵敏度为26.8,响应时间和恢复时间分别约为4 s和10 s,并具有良好的选择性.%Porous micro-spheres of ZnO have been synthesized with Zn(NO3)2﹒6H2O and urea as the raw materials and hex-amine as a surfactant via a hydrothermal method. Structure, morphology, specific surface area, and pore size distribution of ZnO porous micro-sphere are characterized by X-ray diffraction, scanning electron microscopy, and micromeritics AS-AP 2420 apparatus, respectively. Gas sensors are fabricated from the ZnO porous micro-spheres and their gas-sensing properties are measured. The gas sensitivity of sensor samples at different temperatures to acetone gas is examined. Results show that the sensitivity of ZnO porous micro-spheres sensors to 50 ppm acetone gas is 26.8 at 280 ◦C, and the response and recovery durations are 4-10 seconds, respectively. Also, the sensor possesses an excelent selectivity for acetone.