基于钯修饰六方氮化硼的光纤氢气传感器  

Fiber-Optic Hydrogen Sensor Based on Palladium-Modified Hexagonal Boron Nitride

作　　者：丁晖[1] 郭茂森 徐浩东 韩春阳 陈宸 Ding Hui;Guo Maosen;Xu Haodong;Han Chunyang;Chen Chen(School of Electrical Engineering,Xi'an Jiaotong University,Xi'an 710049,Shaanxi,China)

机构地区：[1]西安交通大学电气工程学院,陕西西安710049

出　　处：《光学学报》2023年第22期283-290,共8页Acta Optica Sinica

基　　金：国家自然科学基金面上项目(51777150);国家自然科学基金青年科学基金项目(51907146)。

摘　　要：氢气作为一种可持续、无污染的新型绿色能源,在现代工业中受到了广泛关注。但在存储和使用过程中,氢气容易发生泄漏并引发爆炸,因此对其体积分数进行检测非常重要。为此,提出一种基于钯(Pd)修饰六方氮化硼(hBN)薄膜的新型探针式光纤氢气传感器。讨论hBN薄膜的机械和光学特性,指出其作为Fabry-Perot(F-P)干涉仪反射膜在机械、光学、氢气吸附/脱附速度等领域所具有的显著技术优势;研究hBN表面敷Pd的工艺过程;设计以Pd修饰hBN薄膜为反射膜的光纤F-P腔结构并研究其制备工艺。实验结果表明,所设计的传感器在氢气体积分数为0.02%~0.5%时的检测灵敏度为0.58 pm/10^(-6),对体积分数为0.1%的氢气的响应时间为60 s,且具有重复性好等特点。该传感器结构紧凑、耐腐蚀,在电力变压器油中氢气检测等方面具有潜在的技术优势。Objective As a green and renewable energy source,hydrogen(H2)has caught extensive attention due to its excellent combustion performance and non-polluting characteristics.However,H2 is a volatile,flammable,and explosive gas that faces risks during its storage,transportation,and utilization.Therefore,the development of online sensors for accurately detecting hydrogen concentration is an effective way to prevent explosive accidents.Fiber-optic hydrogen sensors based on Fabry-Perot(F-P)interferometer have been extensively investigated because of their electromagnetic interference resistance,corrosion resistance,and easy integration.The detection performance of F-P cavity-type fiber-optic hydrogen sensors depends mainly on the characteristics of hydrogen-sensitive films composed of palladium(Pd)and substrate.The results show that the thinner thickness of the Pd leads to faster sensor response,and the thinner thickness of the substrate brings about higher sensor sensitivity.In practice,the thickness of the Pd layer can be controlled by the preparation process,while that of the substrate layer is limited by various factors such as the mechanical strength of the material,and it is difficult to both achieve the desired thickness and ensure the mechanical strength.We propose and fabricate a fiber-optic hydrogen sensor based on Pd-modified hexagonal boron nitride(hBN)films.With the nanoscale thickness and high mechanical strength of hBN,the sensor features high sensitivity,fast response,and excellent repeatability.Methods We put forward an F-P type fiber-optic hydrogen sensor based on Pd/hBN films.The Pd/hBN film and the fiber end facet act as two partially reflective mirrors,forming a low-fitness flexible F-P interferometer(Fig.1).When exposed to H2,the Pd/hBN film adsorbs and dissociates H2 molecules.Subsequently,hydrogen atoms diffuse into the Pd film to form PdHx,which results in the expansion of the Pd lattice and then the deformation of the Pd/hBN film(Fig.2).The ultrathin Pd film promotes the rapid dissociation of H2

关 键 词：传感器 氢气体积分数 氮化硼 Fabry-Perot干涉 在线测量 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]