CTAB辅助合成氧化钨及其对乙二醇甲醚的气敏特性

CTAB-Assisted Synthesis and 2-Methoxyethanol Gas Sensing Properties of WO_(3)

以十六烷基三甲基溴化铵(CTAB)为表面活性剂,二水合钨酸钠(Na_(2)WO_(4)·2H_(2)O)为钨源,采用水热法合成纳米氧化钨(WO_(3))。通过扫描电子显微镜(SEM)、X射线衍射仪(XRD)和X射线光电子能谱仪(XPS)对WO_(3)的表面形貌、晶体结构和化学成分进行表征,测试其对乙二醇甲醚的气敏特性,研究CTAB对WO_(3)的形貌、晶体结构和乙二醇甲醚气敏特性的影响。结果表明,CTAB可调控WO_(3)的形貌,添加质量分数5%的CTAB不仅将WO_(3)的形貌由不规则的纳米颗粒调控为疏松的纳米片状,而且提高了其对乙二醇甲醚的气敏特性,在最佳工作温度370℃下其对体积分数为1×10^(-4)的乙二醇甲醚的响应值达15.1,并且具有良好的重复性、长期稳定性与气体选择性。最后探讨了WO_(3)对乙二醇甲醚的气敏机理。

With cetyltrimethylammonium bromide(CTAB)as surfactant,sodium tungstate dehydrate(Na2WO4·2H2O)as tungsten source,nano-WO_(3)was synthesized by hydrothermal method.The surface morphology,crystal structure and chemical composition of WO_(3)were characterized by scanning electron microscope(SEM),X-ray diffractometer(XRD)and X-ray photoelectron spectrometer(XPS).The gas sensing properties of WO_(3)to 2-methoxyethanol gas were tested.The effects of CTAB to the morphology,crystal structure and 2-methoxyethanol gas sensing properties of WO_(3)were studied.The results show that CTAB can control the morphology of WO_(3).The addition of mass fraction 5%CTAB can regulate the morphology of WO_(3)from irregular nanoparticles to loose nanosheets,and improve its gas sensing properties to 2-methoxyethanol.At the optimal operating temperature of 370℃,the response of WO_(3)to 2-methoxyethanol with a volume fraction of 1×10-4 reaches 15.1.It also has good repeatability,long-term stability and gas selectivity.Finally,the gas sensing mechanism of WO_(3)to 2-methoxyethanol was discussed.