Yeshchenko O A, Malynych S Z, Polomarev S O, Galabura Yu, Chumanov G, Luzinov I
Department of Physics, Taras Shevchenko National University of Kyiv 64/13 Volodymyrs'ka Str. 01601 Kyiv Ukraine
Department of Photonics, National University "Lviv Polytechnic" 12 S. Bandery St 79013 Lviv Ukraine
RSC Adv. 2019 Mar 13;9(15):8498-8506. doi: 10.1039/c9ra00498j. eCollection 2019 Mar 12.
We have demonstrated the capability of a nanocomposite film made of a 2D array of Ag nanoparticles embedded into a poly(glycidyl methacrylate), PGMA, matrix to monitor the presence of organic vapors in the atmosphere. Specifically, changes in the extinction spectra of the submicron nanocomposite film are used to sense the vapors. The transformations of the spectra are fully reversible and reproducible upon multiple exposures. We associate this reversibility and reproducibility with the construction of the nanocomposite film where the cross-linked PGMA network is able to spatially restore its structure upon deswelling. The structure of the extinction spectrum of the film is governed by a collective surface plasmon mode excited in the Ag NPs array. It was found that spectral bands associated with normal and tangential components of the plasmon mode change their width and position when the nanocomposite is exposed to organic vapors. This is due to increasing the spacing between neighboring NPs and a decrease of the refractive index of the polymer caused by swelling of the PGMA matrix. Therefore, the level of spectral transformation is directly related to the level of polymer-solvent thermodynamic affinity where the higher affinity corresponds to the higher level of the swelling. Therefore, we expect that the nanocomposite films (when designed for a particular solvent) can be effectively used as a sensing element in a low-cost volatile organic compounds (VOC) sensor device operating in visual light.
我们已经证明了一种纳米复合薄膜的能力，该薄膜由嵌入聚（甲基丙烯酸缩水甘油酯）（PGMA）基质中的二维银纳米颗粒阵列制成，可用于监测大气中有机蒸汽的存在。具体而言，亚微米级纳米复合薄膜消光光谱的变化被用于检测蒸汽。光谱的变化在多次暴露后是完全可逆且可重复的。我们将这种可逆性和可重复性与纳米复合薄膜的结构联系起来，其中交联的PGMA网络在去溶胀时能够在空间上恢复其结构。薄膜消光光谱的结构由银纳米颗粒阵列中激发的集体表面等离子体模式决定。研究发现，当纳米复合材料暴露于有机蒸汽时，与等离子体模式的法向和切向分量相关的光谱带会改变其宽度和位置。这是由于相邻纳米颗粒之间的间距增加以及PGMA基质溶胀导致聚合物折射率降低所致。因此，光谱转变的程度与聚合物 - 溶剂热力学亲和力的程度直接相关，其中较高的亲和力对应于较高的溶胀程度。因此，我们预计（当针对特定溶剂进行设计时）纳米复合薄膜可以有效地用作在可见光下工作的低成本挥发性有机化合物（VOC）传感器装置中的传感元件。
