Chemical Potential Shift in Doped Mott-insulators for Energy Storage Applications

Abstract

This work explores the unique character of strongly correlated systems, specifically Mott-insulators, in the context of battery electrode materials. The study investigates the correlation between the proposed chemical potential evolution and charge storage performance in transition metal oxide-based electrodes. The hypothesis suggests that doping a Mott insulator reduces the Hubbard Coulomb interaction, which could slow down the chemical shift and result in enhanced charge storage capabilities compared to classic band insulators. The results support the hypothesis through a systematic comparison of selected transition metal oxide-based electrodes (Cu, Mn, Co, and Fe oxide electrodes). Furthermore, a toy model is employed to investigate the shift in chemical potential with doping-dependent U using DFT+U calculation, aiming to visualize the chemical potential evolution in Mott-insulators relevant to their application as battery electrodes. This study provides valuable insights into how strongly correlated materials, especially Mott-insulators, contribute to the advancement of energy storage technologies.