MFI分子筛膜在光纤微谐振器上的合成及表征

采用原位水热合成法,分别采用四丙基氢氧化铵(TPAOH)和正丁胺(NBA)为模板剂,在光纤微谐振器表面成功制备出MFI沸石分子筛膜.用X射线衍射(XRD)和扫描电镜(SEM)对膜的物相结构和晶体形貌表征分析可以看出,用四丙基氢氧化铵(TPAOH)为模板剂合成出的沸石晶体具有规则的六棱柱外形,晶粒大小约2 μm,而用正丁胺(NBA)为模板剂合成出的沸石晶体没有规则外形,晶粒大小约为500 nm.采用镀有沸石的长周期光栅(LPFG)检测体积分数为5％丙酮气体,长周期光栅的谐振波长蓝移了2 nm.沸石膜在光纤微谐振表面的合成可用于精密传感器的开发.

Synthesis and characterization of MFI molecular sieve membranes on optical fiber micro-resonators surface

Preparation of MFI zeolite molecular sieve membranes on optical fiber micro-resonators by using TPAOH and NBA as templates was investigated by in situ hydrothermal crystallization.Crystal structure and surface morphology of the obtained membranes were characterized by XRD and SEM.It is showed that good zeolite membranes by using TPAOH and NBA as templates was synthesized.Crystals with the size of about 2 μm synthesized by using TPAOH as template have regular coffin shape,while crystals with the size of about 500 nm synthesized by using NBA as template have no regular shape.Furthermore,the MFI zeolite-LPFG sensor was tested for detection of 5% volume fraction acetone gas.The resonant wavelength of LPFG shifted about 2nm toward smaller wavelength.Upon loading analyte molecules,the refractive index of the MFI zeolite changes in the close of the fiber index where the micro-resonator has a large response to achieve high sensitivity.