Nanoscale evolution of interface morphology during electrodeposition

Area of Science:

• Electrochemistry
• Materials Science
• Surface Science

Background:

• Controlling interfacial morphology is critical for electrochemical applications, including nanomanufacturing and battery technology.
• Understanding the dynamics of electrochemical growth fronts at nanoscale is essential for optimizing material deposition.
• Existing theories often simplify the complex interplay of kinetics and diffusion at the growth interface.

Purpose of the Study:

• To quantify the evolution of an electrochemical growth front at unexplored length and time scales.
• To investigate the underlying physics governing the roughening of electrodeposited copper.
• To explore strategies for morphological control during electrochemical deposition.

Main Methods:

• Utilized liquid cell electron microscopy (LCEM) for in-situ observation of electrochemical processes.
• Performed galvanostatic deposition of copper from an acidic electrolyte.
• Analyzed growth front evolution using established theories of kinetic and diffusion-limited roughening.

Main Results:

• Observed an initial growth phase consistent with kinetic roughening theory.
• Identified a subsequent, faster roughening phase indicative of diffusion-limited growth.
• Found a significant delay in the onset of roughening, suggesting the crucial role of lateral ion diffusion.

Conclusions:

• Electrochemical growth fronts exhibit distinct regimes governed by kinetic and diffusion processes.
• Lateral ion diffusion plays a significant role in delaying and influencing interfacial roughening.
• Morphological control can be achieved through strategies like pulse plating and electrolyte additive modification.