Molecular Perspectives on the Multilayered Polyelectrolyte-Based Electrodes Performance in Supercapacitors

The layer-by-layer (LBL) deposition of polyelectrolytes presents a promising approach for designing advanced electrode materials for energy storage devices such as supercapacitors. This study employs coarse-grained molecular dynamics (CGMD) simulations to investigate LBL polyelectrolyte-based electrodes' structural formation and electrochemical performance in supercapacitor applications. The impact of polyelectrolyte ionization degree on multilayer formation, interdiffusion, and stratification is systematically analyzed. The findings reveal that a higher degree of ionization leads to enhanced layer separation and surface charge density, significantly influencing the electrical double-layer (EDL) formation and charge storage capability in supercapacitors. Electrochemical analyses, including charge density profiles, electrostatic potential distributions, and integral capacitance calculations, demonstrate that electrodes with higher degrees of ionization exhibit increased capacitance and energy density. Additionally, variations in electrolyte ion size impact charge accumulation and EDL thickness, influencing the overall supercapacitor performance. The study provides critical insights into the molecular mechanisms governing LBL-assembled polyelectrolyte electrodes and establishes guidelines for optimizing electrode design for next-generation energy storage technologies.