Ionic Liquid-Packed Microfluidic Device with Non-Planar Microelectrode as a Miniaturized Electrochemical Gas Sensor
Ionic Liquid-Packed Microfluidic Device with Non-Planar Microelectrode as a Miniaturized Electrochemical Gas Sensor
复制标题
具有非平面微电极的离子液体封装微流体装置作为小型化电化学气体传感器
DOI：
10.1149/1945-7111/aced6e
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发表时间：
2023
影响因子：
3.9
通讯作者：
Basuray, Sagnik
中科院分区：
文献类型：
--
作者：
Kaaliveetil, Sreerag;Lee, Yun-Yang;Li, Zhenglong;Cheng, Yu-Hsuan;Menon, Niranjan Haridas;Dongare, Saudagar;Gurkan, Burcu;Basuray, Sagnik
将换能器/传感材料集成到微流体平台中增强了气体传感器的灵敏度、选择性和响应时间，同时促进了小型化。在这份手稿中，微流体与非平面微电极阵列和功能化离子液体（IL）相结合，开发出一种新型的小型化电化学气体传感器架构。该传感器采用IL 1-乙基-3-甲基咪唑鎓2-氰基吡咯烷([EMIM][2-CNpyr])作为电解质和捕获分子来检测二氧化碳(CO 2)。该传感器的三层架构由微通道组成，IL 夹在含有微电极阵列的载玻片之间，形成非平面结构。这种设计有利于电场穿透 IL，捕获整个通道体积中的 CO 2 结合扰动，从而提高灵敏度。 CO 2 与 [EMIM][2-CNpyr] 结合生成羧酸盐 ([EMIM]+-CO2−])、氨基甲酸盐 ([2-CNpyr]-CO2−]) 和吡咯-2-甲腈 (2-CNpyrH) 物质，从而显着降低电导率。粘度也增加，导致电导率进一步下降。这些累积效应增加了阻抗谱中的电荷转移电阻，从而允许使用朗缪尔等温线获得线性校准曲线。 CO 2 检测的灵敏度和再现性通过使用校准曲线的两种电极配置来证明。开发的传感器为未来的应用提供了一个多功能平台。
Integrating transducer/sensing materials into microfluidic platforms has enhanced gas sensors' sensitivity, selectivity, and response time while facilitating miniaturization. In this manuscript, microfluidics has been integrated with non-planar microelectrode array and functionalized ionic liquids (ILs) to develop a novel miniaturized electrochemical gas sensor architecture. The sensor employs the IL 1-ethyl-3-methylimidazolium 2-cyanopyrolide ([EMIM][2-CNpyr]) as the electrolyte and capture molecule for detecting carbon dioxide (CO 2). The three-layer architecture of the sensor consists of a microchannel with the IL sandwiched between glass slides containing microelectrode arrays, forming a non-planar structure. This design facilitates electric field penetration through the IL, capturing CO 2 binding perturbations throughout the channel volume to enhance sensitivity. CO 2 binding with [EMIM][2-CNpyr] generates carboxylate ([EMIM]+-CO2−]), carbamate ([2-CNpyr]-CO2−]), and pyrrole-2-carbonitrile (2-CNpyrH) species, significantly decreasing the conductivity. The viscosity is also increased, leading to a further decrease in conductivity. These cumulative effects increase charge transfer resistance in the impedance spectrum, allowing a linear calibration curve obtained using Langmuir Isotherm. The sensitivity and reproducibility in CO 2 detection are demonstrated by two electrode configurations using the calibration curve. The developed sensor offers a versatile platform for future applications.