Wang Xu-Ming, Li Xin, Liu Wei-Hua, Han Chuan-Yu, Wang Xiao-Li
Department of Microelectronics, Xi'an Jiaotong University, Xi'an 710049, China.
School of Physics, Xi'an Jiaotong University, Xi'an 710049, China.
Materials (Basel). 2021 Jan 14;14(2):388. doi: 10.3390/ma14020388.
In order to address problems of safety and identification in gas detection, an optical detection method based on surface enhanced Raman scattering (SERS) was studied to detect ethanol vapor. A SERS device of silver nanoparticles modified polyvinylpyrrolidone (PVP) was realized by freeze-drying method. This SERS device was placed in a micro transparent cavity in order to inject ethanol vapor of 4% and obtain Raman signals by confocal Raman spectrometer. We compared different types of SERS devices and found that the modification of polyvinylpyrrolidone improves adsorption of ethanol molecules on surfaces of silver nanoparticle, and finally we provide the mechanism by theory and experiment. Finite Difference Time Domain(FDTD) simulation shows that single layer close-packed Ag nanoparticles have strong local electric field in a wide spectral range. In this study, we provide a case for safety and fingerprint recognition of ethanol vapor at room temperature and atmospheric pressure.
为了解决气体检测中的安全性和识别问题，研究了一种基于表面增强拉曼散射（SERS）的光学检测方法来检测乙醇蒸气。通过冷冻干燥法制备了银纳米颗粒修饰聚乙烯吡咯烷酮（PVP）的SERS装置。将该SERS装置置于微型透明腔中，注入4%的乙醇蒸气，并用共焦拉曼光谱仪获取拉曼信号。比较了不同类型的SERS装置，发现聚乙烯吡咯烷酮的修饰提高了乙醇分子在银纳米颗粒表面的吸附，最后从理论和实验两方面给出了作用机理。时域有限差分（FDTD）模拟表明，单层密排银纳米颗粒在较宽光谱范围内具有较强的局部电场。本研究为室温常压下乙醇蒸气的安全性和指纹识别提供了一个实例。
