Synergistic Static and Dynamic Interfacial Regulation Toward Robust Zinc Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Computational Chemistry

Background:

• Aqueous zinc (Zn) metal batteries (AZMBs) offer sustainable energy storage potential.
• Interfacial instability, caused by water-rich electric double layers (EDLs), hinders AZMB development.
• Disordered EDLs lead to parasitic reactions and reduced battery lifespan.

Purpose of the Study:

• To develop a screening strategy for identifying cationic regulators to stabilize the EDL in AZMBs.
• To understand how these regulators reshape the EDL structure and improve interfacial properties.
• To enable predictive and scalable additive screening for enhanced AZMB performance.

Main Methods:

• Density functional theory (DFT) and molecular dynamics (MD) simulations were employed.
• A screening strategy was established to identify effective cationic regulators.
• Machine learning frameworks were developed for predictive additive screening.

Main Results:

• 1-ethyl-3-methylimidazolium demonstrated strong interfacial affinity, creating a hydrophobic layer for 'static passivation'.
• Sodium ions provided 'dynamic regulation' by homogenizing Zn2+ flux and lowering desolvation energy.
• The dual-cation strategy resulted in a water-poor, ordered EDL, enabling stable Zn anodes (>5000 h, 99.73% Coulombic efficiency).

Conclusions:

• A computational screening strategy effectively identifies cationic regulators for AZMBs.
• The dual-cation approach significantly enhances EDL stability and battery performance.
• Mechanistic insights guided the development of a machine learning framework for scalable additive discovery.