Jun Baek
Advisor: Prof. Seung Soon Jang

will propose a doctoral thesis entitled,

Multi-scale Computational Investigation of Interfacial Dynamics in Zinc-ion Batteries

On

Tuesday, April 28 at 12:00 pm
MRDC 4211

And

Virtually via

https://teams.microsoft.com/meet/24173259120565?p=3RRFE13az92HpDpwO2 

Committee
            Prof. Seung Soon Jang – School of Materials Science and Engineering (advisor)
            Prof. Matthew McDowell – School of Materials Science and Engineering
            Prof. Emma Hu – School of Materials Science and Engineering

      Prof. Marta Hatzell - School of Mechanical Engineering

      Prof. Julia Yang - School of Chemical and Biological Engineering

Abstract

Aqueous zinc-ion batteries (AZIBs) have emerged as a compelling alternative for next-generation energy storage systems due to their inherent safety, cost-effectiveness, and environmental sustainability. However, the practical deployment of AZIBs is severely hindered by fundamental challenges at the zinc anode interface, including uncontrolled dendritic growth, hydrogen evolution reactions (HER), and surface corrosion. This research proposes a multi-scale computational framework—integrating density functional theory (DFT), molecular dynamics (MD), and machine-learned interatomic potentials (MLIP)—to design high-performance zinc anode protective layers and optimize electrolyte systems.

The first part of this work investigates the atomic-scale mechanisms of a zinc-doped polypyrrole (Zn-doped PPy) conductive polymer as a functional protective layer. Using DFT calculations, we analyze the structural and electronic properties of PPy, demonstrating that Zn doping at nitrogen sites significantly enhances electrical conductivity by reducing the bandgap and creates potent nucleation sites for uniform Zn deposition. Furthermore, the synergistic effect of incorporating carbon nanotubes (CNTs) into the Zn-doped PPy matrix is explored, focusing on the enhanced mechanical adhesion and the formation of a stable, conductive network that effectively regulates the electric double layer.

The second phase of the research focuses on electrolyte engineering through MD simulations. We examine the solvation and desolvation dynamics of zinc ions in aqueous environments, specifically investigating the impact of organic additives such as ethylene glycol (EG). By analyzing the competitive coordination between water molecules and additives within the Zn2+ solvation shell, we evaluate the advantages and trade-offs of additive engineering in suppressing water-induced side reactions while maintaining high ionic conductivity.

Finally, to bridge the gap between atomic-level interactions and mesoscopic electrochemical behavior, MLIPs are developed and deployed to simulate large-scale zinc deposition processes. This integrated approach allows for a comprehensive analysis of dendrite inhibition and the evolution of the electrode-electrolyte interface. The findings of this research will provide fundamental theoretical insights and design principles for developing dendrite-free, long-life aqueous zinc-ion batteries for large-scale energy storage applications.