Remote Detection of HCN, HF, and Nerve Agent Vapors Based on Self-Referencing, Dye-Impregnated Porous Silicon Photonic Crystals
Remote Detection of HCN, HF, and Nerve Agent Vapors Based on Self-Referencing, Dye-Impregnated Porous Silicon Photonic Crystals
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DOI：
10.1021/acssensors.0c01931
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发表时间：
2021-02-26
期刊：
影响因子：
8.9
通讯作者：
Sailor, Michael J.
中科院分区：
文献类型：
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作者：
Lu, Yi-Sheng;Vijayakumar, Sanahan;Sailor, Michael J.
从多孔硅(PSI)制备一维光子晶体，并将其浸渍化学特定的比色指示剂染料，以提供用于选择性检测氟化氢(HF)、氰化氢(HCN)和化学神经毒剂氟磷酸二异丙酯(DFP)的自参考蒸汽传感器。该光子晶体制备有两个阻挡带：一个与相关被激活的指示剂染料的光吸收值重合，另一个在光谱上清晰的区域，以提供参考。然后用十八烷基硅烷修饰PSI样品的内部孔壁以提供疏水内部，然后将感兴趣的指示剂染料加载到介孔基质中。远程分析物检测是通过测量白光反射光谱中两个阻挡带的强度比来实现的，这提供了一种可靠地检测指示剂染料的比色变化的方法。根据相关试剂的特异性选择指示染料：罗丹明-咪唑(RDI)用于HF和DFP，单氰基钴酰胺(MCBI)用于HCN。比率读数允许检测浓度(分别为14ppm和5ppm)低于各自的IDLH(对生命和健康直接危险)浓度(HF为30ppm；HCN为50ppm)的浓度；还显示了浓度为114 ppb的DFP的检测。该方法对潜在的干扰物，如氨、氯化氢、辛烷，以及称为EPA-14A的43种VOCs混合物，以及相对湿度(20-80%RH)的变化不敏感。证明了添加到EPA到-14A复杂混合物中的HF和HCN的检测。该方法为构建稳健的化学毒剂远程检测系统提供了一种通用手段。
A one-dimensional photonic crystal is prepared from porous silicon (pSi) and impregnated with a chemically specific colorimetric indicator dye to provide a self-referenced vapor sensor for the selective detection of hydrogen fluoride (HF), hydrogen cyanide (HCN), and the chemical nerve agent diisopropyl fluorophosphate (DFP). The photonic crystal is prepared with two stop bands: one that coincides with the optical absorbance of the relevant activated indicator dye and the other in a spectrally "clear" region, to provide a reference. The inner pore walls of the pSi sample are then modified with octadecylsilane to provide a hydrophobic interior, and the indicator dye of interest is then loaded into the mesoporous matrix. Remote analyte detection is achieved by measurement of the intensity ratio of the two stop bands in the white light reflectance spectrum, which provides a means to reliably detect colorimetric changes in the indicator dye. Indicator dyes were chosen for their specificity for the relevant agents: rhodamine-imidazole (RDI) for HF and DFP, and monocyanocobinamide (MCbi) for HCN. The ratiometric readout allows detection of HF and HCN at concentrations (14 and 5 ppm, respectively) that are below their respective IDLH (immediately dangerous to life and health) concentrations (30 ppm for HF; 50 ppm for HCN); detection of DFP at a concentration of 114 ppb is also demonstrated. The approach is insensitive to potential interferents such as ammonia, hydrogen chloride, octane, and the 43-component mixture of VOCs known as EPA TO-14A, and to variations in relative humidity (20-80% RH). Detection of HF and HCN spiked into the complex mixture EPA TO-14A is demonstrated. The approach provides a general means to construct robust remote detection systems for chemical agents.