Depth-Sensitive Subsurface Imaging of Polymer Nanocomposites Using Second Harmonic Kelvin Probe Force Microscopy
Depth-Sensitive Subsurface Imaging of Polymer Nanocomposites Using Second Harmonic Kelvin Probe Force Microscopy
复制标题
DOI：
10.1021/nn507019c
复制
发表时间：
2015-03-01
期刊：
影响因子：
17.1
通讯作者：
Avila, Alba
中科院分区：
文献类型：
--
作者：
Alejandro Castaneda-Uribe, Octavio;Reifenberger, Ronald;Avila, Alba
我们使用开尔文探针力显微镜 (KPFM) 中的二次谐波映射研究聚合物纳米复合材料的地下成像的深度灵敏度和空间分辨率。该方法允许通过电容梯度（0c704 图）可视化埋藏单壁碳纳米管 (SWCNT) 的聚集和渗透。我们开发了一种多层样品，其中纯聚酰亚胺 (PI) 薄层（每层类似于 80 nm）依次旋涂在分散良好的 SWCNT/聚酰亚胺 (PI) 纳米复合薄膜上。多层纳米复合材料系统允许获取偏导数 C/偏导数 z我们检测了样品同一区域不同深度的碳纳米管的三维渗滤网络图像，并注意到，随着埋藏碳纳米管深度的增加，空间分辨率逐渐恶化。偏导数 C/偏导数 z 与碳纳米管深度的计算趋势将灵敏度和深度分辨率与场穿透和扩散相关联，并为三维地下结构重建提供了可能的方法。用于纳米复合材料应用的无损三维断层扫描和纳米计量技术。
We study the depth sensitivity and spatial resolution of subsurface imaging of polymer nanocomposites using second harmonic mapping in Kelvin Probe Force Microscopy (KPFM). This method allows the visualization of the clustering and,percolation of buried Single Walled Carbon Nanotubes (SWCNTs) via capacitance gradient (0c704 maps. We develop a multilayered sample where thin layers of neat Polyimide (PI) (similar to 80 nm per layer) are sequentially spin-coated on well-dispersed SWCNT/Polyimide (PI) nanoconnposite films. The multilayer nanocomposite system allows the acquisition of partial derivative C/partial derivative z images of three-dimensional percolating.networks of SWCNTs at different depths in the same region of the sample. We detect CNTs at a depth of similar to 430,nm, and notice that the spatial resolution progressively deteriorates with increasing depth of the buried CNTs. Computational trends of partial derivative C/partial derivative z vs CNT depth correlatethe sensitivity and depth resolution with field penetration and spreading, and enable.a possible approach to three-dimensional subsurface structure reconstruction. The results open the door to nondestructive, three-dimensional tomography and nanometrology techniques for nanocomposite applications.