氧化锌纳米纤维的制备及其氨气气敏特性

Preparation and ammonia gas-sensitive properties of ZnO nanofibres

采用静电纺丝技术制备了具有多孔结构的ZnO纳米纤维,通过扫描电子显微镜(SEM)、X射线衍射(XRD)和X射线能量色散谱(EDS)对ZnO纳米纤维的形貌、晶体结构和组成成分进行了表征。将上述材料制成气体传感器,对氨气进行了气敏性能测试。实验结果表明,由ZnO纳米纤维制成的气体传感器在室温下对氨气具有较高的灵敏度和较低的检测限,对300ppm氨气的响应值约为65%,响应时间和恢复时间分别为70 s和60 s,对10ppm氨气的响应值约为3.3%,并且具有良好的选择性和长期稳定性。由于ZnO纳米纤维表面形成了特殊的多孔结构,为氧化还原反应提供了更多的氧空位和活性位点,有利于气体的吸附,提高了传感器对氨气的气敏性能,使其在实际应用中极具前景。

ZnO nanofibers with porous structure were prepared by electrostatic spinning technique.The morphology,crystal structure and composition of ZnO nanofibers were characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD)and X-ray energy dispersive spectroscopy(EDS)analysis.The above materials were made into gas sensors and their ammonia gas-sensitive performance was investigated.The experimental results show that the gas sensor prepared with ZnO nanofibers has high sensitivity and low detection limit for the ammonia gas at room temperature.The sensor has a response value of about 65%for 300ppm ammonia gas,response time and recovery time of 70 and 60 s,respectively,and a response value of about 3.3%for 10ppm ammonia gas,and has good selectivity and long-term stability.The porous structure formed on the surface of ZnO nanofibers provides more oxygen vacancies and active sites for the redox reaction,which is favorable for gas adsorption,so the gas-sensitive performance of the sensor for ammonia gas can be improved,making it a good candidate for practical application.