Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, PA, 19104, USA.
Department of Materials Science and Engineering, University of California-Los Angeles, Los Angeles, CA, 90095, USA.
Nat Commun. 2017 Dec 19;8(1):2174. doi: 10.1038/s41467-017-02364-9.
Control of interfacial morphology in electrochemical processes is essential for applications ranging from nanomanufacturing to batteries. Here, we quantify the evolution of an electrochemical growth front, using liquid cell electron microscopy to access unexplored length and time scales. During galvanostatic deposition of copper from an acidic electrolyte, we find that the growth front initially evolves consistent with kinetic roughening theory. Subsequently, it roughens more rapidly, consistent with diffusion-limited growth physics. However, the onset of roughening is strongly delayed compared to expectations, suggesting the importance of lateral diffusion of ions. Based on these growth regimes, we discuss morphological control and demonstrate the effects of two strategies, pulse plating and the use of electrolyte additives.
电化学过程中界面形态的控制对于从纳米制造到电池等应用至关重要。在这里,我们使用液相电子显微镜来获取以前未探索过的长度和时间尺度,从而定量研究电化学生长前沿的演变。在酸性电解质中进行铜的恒电流沉积时,我们发现生长前沿最初的演变符合动力学粗化理论。随后,它的粗化速度更快,符合扩散限制生长物理。然而,与预期相比,粗化的开始被强烈延迟,这表明离子的横向扩散很重要。基于这些生长阶段,我们讨论了形态控制,并展示了两种策略的效果,即脉冲电镀和使用电解质添加剂。