Milenković Mila, Saeed Warda, Yasir Muhammad, Sredojević Dusan, Budimir Milica, Stefanović Andjela, Bajuk-Bogdanović Danica, Jovanović Svetlana
Vinča Institute of Nuclear Sciences-National Institute of the Republic of Serbia, University of Belgrade, Mike Petrovića Alasa 12-14, Vinča, 11351 Belgrade, Serbia.
Division of Microrobotics and Control Engineering, Department of Computing Science, Carl von Ossietzky Universität Oldenburg, 26129 Oldenburg, Germany.
Int J Mol Sci. 2024 Dec 13;25(24):13401. doi: 10.3390/ijms252413401.
Technological development has led to the need for materials able to block electromagnetic waves (EMWs) emitted from various devices. EMWs could negatively affect the working performance and lifetime of multiple instruments and measuring devices. New EMW shielding materials are being developed, while among nanomaterials, graphene-based composites have shown promising features. Herein, we have produced graphene oxide (GO), silver nanowires (AgNWs) composites, by varying the mass ratios of each component. UV-Vis, infrared, Raman spectroscopies, and thermogravimetric analysis proved the establishment of the interactions between them. For the first time, the strength and the nature of the interaction between GO sheets with various levels of oxidation and AgNWs were investigated using density function theory (DFT). The interaction energy between ideal graphene and AgNWs was calculated to be -48.9 kcal/mol, while for AgNWs and GO, this energy is almost doubled at -81.9 kcal/mol. The DFT results confirmed the interfacial polarization at the heterointerface via charge transfer and accumulation at the interface, improving the efficacy of EMW shielding. Our results indicated that AgNWs create a compact complex with GO due to charge transfer between them. Charge redistributions in GO-AgNWs composites resulted in an improved ability of the composite to block EMWs compared to GO alone.
技术发展导致需要能够阻挡各种设备发出的电磁波(EMW)的材料。电磁波会对多种仪器和测量设备的工作性能和使用寿命产生负面影响。新型电磁波屏蔽材料正在研发中,而在纳米材料中,基于石墨烯的复合材料已展现出有前景的特性。在此,我们通过改变各组分的质量比制备了氧化石墨烯(GO)与银纳米线(AgNWs)的复合材料。紫外可见光谱、红外光谱、拉曼光谱以及热重分析证实了它们之间相互作用的形成。首次使用密度泛函理论(DFT)研究了不同氧化程度的氧化石墨烯片层与银纳米线之间相互作用的强度和性质。理想石墨烯与银纳米线之间的相互作用能计算为-48.9千卡/摩尔,而银纳米线与氧化石墨烯之间的该能量几乎翻倍,为-81.9千卡/摩尔。DFT结果通过界面处的电荷转移和积累证实了异质界面处的界面极化,提高了电磁波屏蔽的效能。我们的结果表明,由于银纳米线与氧化石墨烯之间的电荷转移,银纳米线与氧化石墨烯形成了紧密的复合物。与单独的氧化石墨烯相比,氧化石墨烯-银纳米线复合材料中的电荷重新分布导致该复合材料阻挡电磁波的能力得到提高。