Stability and temporal decay of nanopatterned tribocharge on nanotextured elastomer surfaces
Stability and temporal decay of nanopatterned tribocharge on nanotextured elastomer surfaces
复制标题
DOI：
10.1016/j.nanoen.2020.105441
复制
发表时间：
2021-01-01
期刊：
影响因子：
17.6
通讯作者：
Kim, Jaeyoun
中科院分区：
文献类型：
--
作者：
Ji, Myung Gi;Li, Qiang;Kim, Jaeyoun
纳米结构弹性体表面的接触通电通常会产生纳米图案的摩擦电荷，这对科学和实际目的都很有用。为了持续利用纳米化摩擦电荷，必须对其稳定性和时间行为进行表征和研究。然而，这是一项极具挑战性的任务，因为它需要在纳米尺度的空间分辨率下对摩擦电荷进行长期、反复的探测。在这项工作中，我们使用开尔文探针力显微镜（KPFM）和静电力显微镜（EFM）对弹性体表面的纳米图案摩擦荷进行了全面的实验研究。KPFM结果的曲线拟合分析不仅肯定了摩擦荷电的时间衰减性质，而且将它们分为两种不同的成分，快速和缓慢衰减，可归因于两种不同的摩擦荷电机制。通过对曲线拟合参数的预约束优化和结果的比较，我们可以将快速和慢速衰减分量分别归因于材料界面的切向滑动和表面法向分离产生的摩擦荷电。该分析还使我们能够从KPFM结果中估计出时不变的“基座”电位，并预测纳米结构弹性体表面存在长期稳定的摩擦电荷。我们在首次测量后的14天通过重新扫描标本实验证实了这一点。这些观察、分析和机械摩擦电荷模型不仅对纳米尺度摩擦电荷的研究人员有益，而且对那些对摩擦电的研究和应用感兴趣的人也有好处。
Contact electrification of nanotextured elastomer surfaces often generates nanopatterned tribocharges that are useful for both scientific and practical purposes. For sustained utilization of the nanopatterned tribocharge, their stability and temporal behavior must be characterized and studied. It is, however, a highly challenging task as it requires long-term, repeated probing of the tribocharge at the nanoscale spatial resolution. In this work, we performed such a comprehensive experimental study of nanopatterned tribocharges on elastomer surfaces using Kelvin probe force microscopy (KPFM) and electrostatic force microscopy (EFM). Curve-fitting analysis of the KPFM results not only affirmed the temporally decaying nature of the tribocharge but also separated them into two distinct, fast and slowly decaying, components that could be attributed to two different tribocharging mechanisms. Through pre-constrained optimization of the curve-fitting parameters and comparison of the results, we could attribute the fast and slow decay components to the tribocharges generated by tangential sliding and surface-normal separation of the material interface, respectively. The analysis also enabled us to estimate time-invariant "pedestal" potentials from the KPFM results and predict the existence of long-term stable tribocharge on the nanotextured elastomer surface. We experimentally confirmed it by re-scanning the specimens 14 days after the initial measurements. The observations, analysis, and the mechano-triboelectric charging model will benefit not only the researchers of nanoscale tribocharges but also those interested in the study and applications of triboelectricity in general.