Lu Yanyan, Yuan Xuzhou, Jia Cuiping, Lei Biao, Zhang Hongwen, Zhao Zhipeng, Zhu Shuyi, Zhao Qian, Cai Weiping
Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China.
Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China.
Nanomaterials (Basel). 2023 Jul 6;13(13):2016. doi: 10.3390/nano13132016.
Volatile organic compounds (VOCs), particularly monoaromatic hydrocarbon compounds (MACHs), pose a potential risk to the atmospheric environment and human health. Therefore, the progressive development of efficient detection methodologies is a pertinent need, which is still a challenge at present. In this study, we present a rapid and sensitive method to detect trace amounts of MACHs using a bifunctional SERS composite substrate. We prepared an Au/SiO enhanced layer and a porous Cu(OH) adsorption layer via microfluidic-assisted gas-liquid interface self-assembly. The composite substrate effectively monitored changes in benzaldehyde using time-varying SERS spectra, and track-specifically identified various VOCs such as benzene, xylene, styrene, and nitrobenzene. In general, the substrate exhibited a rapid response time of 20 s to gaseous benzaldehyde, with a minimum detection concentration of less than 500 ppt. Further experimental assessments revealed an optimum Cu(OH) thickness of the surrounding adsorption layer of 150 nm, which can achieve an efficient SERS response to MACHs. Furthermore, the recoverable and reusable property of the composite substrate highlights its practicality. This study presents a straightforward and efficient approach for detecting trace gaseous VOCs using SERS, with significant implications in the designing of SERS substrates for detecting other VOCs.
挥发性有机化合物（VOCs），特别是单芳烃化合物（MACHs），对大气环境和人类健康构成潜在风险。因此，逐步开发高效的检测方法是一项迫切需求，而目前这仍是一项挑战。在本研究中，我们提出了一种使用双功能表面增强拉曼光谱（SERS）复合基底检测痕量MACHs的快速灵敏方法。我们通过微流控辅助气液界面自组装制备了金/二氧化硅增强层和多孔氢氧化铜吸附层。该复合基底利用随时间变化的SERS光谱有效地监测了苯甲醛的变化，并特异性地追踪识别了各种挥发性有机化合物，如苯、二甲苯、苯乙烯和硝基苯。总体而言，该基底对气态苯甲醛的响应时间为20秒，最低检测浓度低于500皮克/升。进一步的实验评估表明，周围吸附层的氢氧化铜最佳厚度为150纳米，这可以实现对MACHs的高效SERS响应。此外，复合基底的可回收和可重复使用特性突出了其实用性。本研究提出了一种使用SERS检测痕量气态挥发性有机化合物的直接有效方法，对设计用于检测其他挥发性有机化合物的SERS基底具有重要意义。
