Optical fibre long period grating gas sensor modified with metal organic framework thin films
Optical fibre long period grating gas sensor modified with metal organic framework thin films
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DOI：
10.1016/j.snb.2015.07.027
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发表时间：
2015-12-31
影响因子：
8.4
通讯作者：
Korposh, Sergiy
中科院分区：
文献类型：
--
作者：
Hromadka, Jiri;Tokay, Begum;Korposh, Sergiy
将分子筛骨架材料ZIF-8和金属有机骨架家族的一种亚族分子筛ZIF-8修饰的长周期光纤光栅(LPG)用于有机气体的检测。采用原位结晶技术，将12.5 mm的六水硝酸锌和25 mm的2-甲基咪唑溶液混合在甲醇中，在液化气表面沉积了ZIF-8薄膜。用扫描电子显微镜对ZIF-8薄膜进行了表征。用椭偏仪测量了经过1、2、3、5和10个生长周期的薄膜的厚度和折射率。X-射线衍射图证实了薄膜的结晶度。液化石油气被设计为在相位匹配转折点运行，以提供最高的灵敏度。传感机理是基于测量化学分子穿透到ZIF-8孔中所引起的薄膜的RI的变化。研究了经ZIF-8分子筛2次和5次生长周期修饰的LPG在甲醇、乙醇、异丙醇和丙酮中的响应。还考察了测量结果对湿度作为干扰参数的敏感性。(C)2015爱思唯尔B.V.保留所有权利。
An optical fibre long period grating (LPG) modified with a thin film of ZIF-8, a zeolitic immidazol framework material and a subgroup of metal organic framework family, was employed for the detection of organic vapours. ZIF-8 films were deposited onto the surface of the LPG using an in-situ crystallization technique by mixing freshly prepared 12.5 mM zinc nitrate hexahydrate and 25 mM 2-metyl-imidazole solutions in methanol. The ZIF-8 film was characterized by scanning electron microscopy. The thickness and refractive index (RI) of films deposited after 1,2,3,5 and 10 growth cycles were determined by using an ellipsometer. The crystallinity of the films was confirmed by X-ray diffraction pattern. The LPG was designed to operate at the phase matching turning point to provide the highest sensitivity. The sensing mechanism is based on the measurement of the change in the RI of the film induced by the penetration of the chemical molecules into the ZIF-8 pores. The responses of LPGs modified with 2 and 5 growth cycles of ZIF-8 to exposure to methanol, ethanol, 2-propanol and acetone were characterised. The sensitivity of the measurements to humidity as an interfering parameter was also investigated. (C) 2015 Elsevier B.V. All rights reserved.