Department of Civil and Environmental Engineering, National University of Singapore, Kent Ridge, Singapore 119260.
Nanoscale. 2012 Aug 21;4(16):5077-81. doi: 10.1039/c2nr31059g. Epub 2012 Jul 9.
This work is concerned with the wrinkling phenomenon observed in an annular graphene sheet under circular shearing at its inner edge. By performing molecular mechanics simulations on the aforementioned loaded annular graphene sheet, it is observed that the unusual wrinkles formed are confined to within an annulus that hugs the perimeter of the inner radius. This confined wrinkling pattern is in contrast to the wrinkling patterns that spread throughout rectangular graphene sheets under tension or shear. The present wrinkling pattern is characterized by a wave number and wrinkle profile. The wave number at the bifurcation wrinkle is found to depend only on the inner radius of the annular graphene and it increases almost linearly with increasing inner radius. The orientation of these developed waves is found to be at a constant angle and independent from the radii ratio of annular graphene. The wrinkle profile in terms of wave amplitude and wavelength depends on the magnitude of the circular shearing. The predictable formation of wrinkles in annular graphene can be exploited for applications in nano-force sensors, tunable magnetic or electronic devices, as well as patterned stretchable electronics.
这项工作关注的是在环形石墨烯片的内边缘进行圆形剪切时观察到的皱折现象。通过对上述加载的环形石墨烯片进行分子力学模拟，观察到形成的异常褶皱局限于内半径周边的环内。与在拉伸或剪切下扩展到整个矩形石墨烯片的褶皱模式相比，这种受限的褶皱模式是不同的。目前的褶皱模式的特征在于波数和褶皱轮廓。在分岔褶皱处的波数仅取决于环形石墨烯的内半径，并且随着内半径的增加几乎呈线性增加。发现这些展开波的取向以恒定角度存在，并且与环形石墨烯的半径比无关。波纹轮廓在波纹幅度和波长方面取决于圆形剪切的大小。在环形石墨烯中可预测的褶皱形成可用于纳米力传感器、可调谐磁或电子器件以及图案化可拉伸电子产品等应用。
