• • Voltage window limitation: Perovskite oxide electrodes in 6 M KOH exhibit a maximum voltage window of <0.5 V due to water decomposition, directly capping energy density; replacing aqueous electrolytes with organic, ionic liquid, or Water-in-Salt systems is critical for exceeding this threshold and enabling higher-energy pseudocapacitors.
• • Oxygen vacancy-mediated mechanism: Energy storage relies on oxygen anion intercalation through abundant oxygen vacancies, inducing reversible Mn valence transitions (Mn2+→Mn3+→Mn4+) in LaMnO3±δ; this surface-controlled Faradaic process avoids bulk diffusion, yielding high rate capability but requiring precise vacancy engineering to maintain capacity retention.
• • Interface reconfiguration: Hydroxyl metal oxides generated on the perovskite surface during electrocycling facilitate interface reconstruction, significantly increasing capacity without foreign substances; this self-improving behavior offers a pathway to mitigate initial capacity fade but demands control over cycling protocols to avoid parasitic reactions.
• • Electronic structure dependence: OH− adsorption capacity, oxygen ion mobility, and conductivity are governed by the localized density of states near the Fermi level and spin-electron states; tuning these electronic parameters through compositional engineering (e.g., K-doping, fluorination) can weaken metal–oxygen bonds and enhance proton migration, directly impacting specific capacity and rate performance.