CNR IMM-Bologna, Via Gobetti, 101, 40129 Bologna, Italy.
Nano Lett. 2012 Oct 10;12(10):5207-12. doi: 10.1021/nl3023737. Epub 2012 Sep 24.
While the unique elastic properties of monolayer graphene have been extensively investigated, less knowledge has been developed so far on folded graphene. Nevertheless, it has been recently suggested that fold-induced curvature (without in-plane strain) could possibly affect the local chemical and electron transport properties of graphene, envisaging a material-by-design approach where tailored membranes are used in enhanced nanoresonators or nanoelectromechanical devices. In this work we propose a novel method combining apparent strain analysis from high-resolution transmission electron microscopy (HREM) images and theoretical modeling based on continuum elasticity theory and tight-binding atomistic simulations to map and measure the nanoscale curvature of graphene folds and wrinkles. If enough contrast and resolution in HREM images are obtained, this method can be successfully applied to provide a complete nanoscale geometrical and physical picture of 3D structure of various wrinkle and fold configurations.
虽然单层石墨烯的独特弹性特性已经得到了广泛的研究，但到目前为止，关于折叠石墨烯的知识还比较少。然而，最近有人提出，褶皱诱导的曲率（没有面内应变）可能会影响石墨烯的局部化学和电子输运性质，可以设想一种通过设计材料的方法，在增强型纳米谐振器或纳米机电设备中使用定制的薄膜。在这项工作中，我们提出了一种新的方法，结合高分辨率透射电子显微镜（HREM）图像中的表观应变分析和基于连续弹性理论和紧束缚原子模拟的理论建模，来映射和测量石墨烯褶皱的纳米级曲率。如果在 HREM 图像中获得足够的对比度和分辨率，这种方法可以成功地应用于提供各种褶皱和折叠结构的 3D 结构的完整纳米级几何和物理图像。
