Dai Zhigao, Mei Fei, Xiao Xiangheng, Liao Lei, Wu Wei, Zhang Yupeng, Ying Jianjian, Wang Lingbo, Ren Feng, Jiang Changzhong
Department of Physics, Hubei Nuclear Solid Physics Key Laboratory and Center for Ion Beam Application, Wuhan University, Wuhan 430072, People's Republic of China.
Nanotechnology. 2015 Mar 27;26(12):125603. doi: 10.1088/0957-4484/26/12/125603. Epub 2015 Mar 6.
We have reported that the Ag nanostructure-based substrate is particularly suitable for surface-enhanced Raman scattering when it is coated with monolayer graphene, an optically transparent and chemistry-inertness material in the visible range. Ag bowtie nanoantenna arrays and Ag nanogrids were fabricated using plasma-assisted nanosphere lithography. Our measurements show that atmospheric sulfur containing compounds are powerless to break in the monolayer graphene to vulcanize the surfaces of the Ag bowtie nanoantenna arrays and Ag nanogrids by various means, including scanning electron microscopy (SEM) and x-ray photoelectron spectroscopy (XPS). Furthermore, the Ag nanostructure substrate coated with the monolayer graphene film shows a larger enhancement of Raman activity and the electromagnetic field than the uncoated substrate. Compared with those of bare Ag nanostructures, the averaged EFs of graphene-film-coated Ag nanostructures were estimated to be about 21 and 5 for Ag bowtie nanoantenna arrays and nanogrids after one month later in air, respectively. These observations are further supported by theoretical calculations.
我们已经报道过，基于银纳米结构的基底在涂覆单层石墨烯时特别适用于表面增强拉曼散射，单层石墨烯在可见光范围内是一种光学透明且化学惰性的材料。使用等离子体辅助纳米球光刻技术制备了银蝴蝶结纳米天线阵列和银纳米网格。我们的测量结果表明，大气中的含硫化合物无法通过包括扫描电子显微镜（SEM）和X射线光电子能谱（XPS）在内 的各种方式穿透单层石墨烯使银蝴蝶结纳米天线阵列和银纳米网格的表面硫化。此外，涂覆有单层石墨烯膜的银纳米结构基底比未涂覆的基底表现出更大的拉曼活性增强和电磁场增强。与裸露的银纳米结构相比，在空气中放置一个月后，涂覆石墨烯膜的银纳米结构对于银蝴蝶结纳米天线阵列和纳米网格的平均增强因子分别估计约为21和5。这些观察结果得到了理论计算的进一步支持。
