ZIF-67修饰WO_(3)纳米片的制备及其气敏性能

Gas sensing performance and preparation of WO_(3) nanosheets decorated by ZIF-67

金属氧化物半导体气敏传感器在有毒有害气体检测领域逐渐表现出巨大的应用前景,但是金属氧化物半导体传感器通常在检测时受环境湿度影响较大,这极大地限制了其应用。本文采用水热法成功在陶瓷管表面原位生长WO_(3)纳米片,并以此为基底,在其表面生长ZIF-67多孔材料,通过调控W和Co的比例制备了不同比例的ZIF-67/WO_(3)复合材料,利用XRD、SEM、FTIR和比表面积测试仪(BET)等方法对所制备的材料进行物相和形貌表征。针对其不同比例的复合材料的气敏性能进行了研究。结果表明:W∶Co摩尔比为1∶1的ZIF-67/WO_(3)(1∶1)复合材料性能最好,在220℃对三乙胺表现出优异的选择性,对体积分数为100×10^(-6)的三乙胺的响应值可达140.34,响应和恢复时间分别为9 s和7 s。研究了空气相对湿度(RH)对ZIF-67/WO_(3)(1∶1)传感器的影响,结果表明,在高达75%RH环境下该材料仍能保持较好的响应值,相对于纯WO_(3)气敏材料具有较好的抗湿性能。

Metal oxide semiconductor gas sensors are exhibiting great application prospects in the field of toxic and hazardous gas detection gradually,but metal oxide semiconductor sensors are commonly affected by ambient humidity during detection,which significantly limits their applications.In this paper,WO_(3)nanosheets were successfully in situ grown on the surface of ceramic tubes by hydrothermal method,and ZIF-67 porous materials were grown on the surface of ceramic tubes using it as substrate.Different ZIF-67/WO_(3)composites were prepared by adjusting the proportion of W and Co.The structures and morphologies of different ZIF-67/WO_(3)composites were analyzed via XRD,SEM,FTIR and BET techniques.The gas sensing properties of the pristine and different ZIF-67/WO_(3)composites are investigated.The results indicate that the ZIF-67/WO_(3)(1∶1)composite which W∶Co molar ratio is 1∶1 has the best performance with excellent selectivity to trimethylamine(TEA)at 220℃,and high response of 140.34 to TEA gas with volume fraction of 100×10^(-6).The response/recovery time is 9 s and 7 s,respectively.The effect of air relative humidity(RH)on the sensors has also studied.The results show that the ZIF-67/WO_(3)(1∶1)sensor can maintain a good response value in an environment humidity up to 75%RH and has a good moisture resistance compared with the pristine WO_(3)gas sensing material.