Yuzhakov Vadim V., Takhistov Pavlo V., Miller Albert E., Chang Hsueh-Chia
Department of Chemical Engineering, University of Notre Dame, Notre Dame, Indiana 46556.
Chaos. 1999 Mar;9(1):62-77. doi: 10.1063/1.166380.
We extend our earlier study of nanoscale pattern formation during electropolishing [Nanotechnology 7, 360 (1996); Phys. Rev. B 56, 12 608 (1997)]. The patterns are attributed to preferential adsorption of organic molecules on the convex portion of the electrode due to its enhanced electric field. This local enhancement occurs because of the effect of surface curvature on the double-layer potential drop. By allowing for transport correction to the double-layer potential drop at thermodynamic equilibrium, we estimate this anodic overpotential to be in the realistic mV range and hence verify the Debye-Huckel approximation used in our model. This small anodic overpotential suggests that pattern formation is a generic electropolishing phenomenon whose only requirement is that the polarizability of the organic additive relative to water must lie within a range specified by our theory. We verify this prediction experimentally with a variety of electrolyte solutions. The voltage ranges for specific hexagonal and ridge patterns are well correlated by our model with only a single parameter. (c) 1999 American Institute of Physics.
我们扩展了早期关于电抛光过程中纳米级图案形成的研究[《纳米技术》7, 360 (1996); 《物理评论B》56, 12608 (1997)]。这些图案归因于有机分子由于电极凸部增强的电场而在其上优先吸附。这种局部增强是由于表面曲率对双层电位降的影响而发生的。通过考虑在热力学平衡时对双层电位降的输运修正，我们估计这种阳极过电位处于实际的毫伏范围内，从而验证了我们模型中使用的德拜 - 休克尔近似。这种小的阳极过电位表明图案形成是一种普遍的电抛光现象，其唯一要求是有机添加剂相对于水的极化率必须处于我们理论所规定的范围内。我们用各种电解质溶液通过实验验证了这一预测。特定六边形和脊状图案的电压范围通过我们的模型仅用一个参数就得到了很好的关联。(c) 1999美国物理研究所。
