Understanding the electric double layer at the electrode–electrolyte interface: Part II - specific adsorption and partial charge transfer

Electrochimica Acta. 2026. Vol. 545. Article 147660.

Daria A. Mazur, Petr E. Brandyshev, Doronin S., Yury A. Budkov

Recent advances in theoretical modelling of the electric double layer (EDL) have significantly improved the
accuracy of key parameters such as differential capacitance and ion profiles, paving the way for molecularlevel
descriptions of electrochemical interfaces. Despite these developments, existing models often lack a
unified physical framework, limiting their ability to capture complex interfacial phenomena such as ion
adsorption and charge transfer-processes critical for next-generation energy devices. In this work, we extend a
recently developed self-consistent field (SCF) theory [D.A. Mazur, et al., ChemPhysChem 2024, e202400650]
to explicitly incorporate ion adsorption and charge transfer effects, enabling a comprehensive and physically
consistent description of the EDL. We applied our model to Ag/aqueous electrolyte interfaces (KPF6, NaF, and
their mixtures), successfully reproducing experimental differential capacitance and qualitatively capturing the
EDL structure, including Stern and diffuse layers, solely through the solution SCF equations without ad hoc
assumptions. Complemented by quantum chemical calculations and ab initio molecular dynamics, our approach
provides new microscopic insights into the EDL and offers a robust foundation for the rational design of
advanced electrochemical systems.

Keywords: двойной электрический слой, перенос заряда, квантовая химия, Electric double layer, модифицированное уравнение Пуассона-Больцмана, Modified Poisson-Boltzmann equation, electrolytes, электролиты, charge transfer, Quantum chemical calculations, Ab initio molecular dynamics (AIMD), квантовая молекулярная динамика, Specific adsorption, специфическая адсорбция

Publication based on the results of: Прогнозирование свойств молекулярных систем: совмещение методов машинного обучения и классических методов моделирования (2026)