Public Abstract

DE-SC0024274: Understanding Solid-Solution-Reaction vs. Solid-Phase-Transformation Competition of Complex Conversion Materials Dominated by Interfacial Kinetics

Award Status: Active

Institution: Catholic University of America, Washington, DC
UEI: C31ES3WEAVQ5
DUNS: 041962788

Most Recent Award Date: 09/05/2025
Number of Support Periods: 3
PM: Henderson, Craig

Current Budget Period: 08/15/2025 - 08/14/2026
Current Project Period: 08/15/2023 - 08/14/2026
PI: Lin, Chuan-Fu

Supplement Budget Period: N/A

Public Abstract

Equilibrium phase transformation and phase competition of complex systems are major subjects of materials science as the outcomes critically determined materials characteristics. However, the phase competition under conditions that deviate from equilibrium are not well studied but offer many opportunities for the exploration of a wide variety of materials properties and responses. The objectives of the project are to understand and reveal which and how the interfacial kinetics can impose interfacial-chemical-mechanical-structural kinetic constraints to control the formation of new phases that further alter the equilibrium phase competitions between solid-solution reaction vs. solid-phase-transformation in complex conversion materials systems. Conversion materials are usually binary or ternary compounds that are promising for high lithium-ion storage capacity (3~5 times higher than the current commercial electrode materials), but the solid-state phase transformations that occur upon lithium uptake hinder high reversibility, which limits their overall application in Li-ion batteries. A new design principle of extending the reversible solid-solution (“intercalation”) phases to higher capacity by controlling the onset of solid-state phase transformation (“conversion”) via interface kinetics will be achieved to benefit the energy storage technology directly by enabling low-cost, reversible, cobalt-free, high-capacity conversion electrodes. The scientific impacts of this project are not only the improved reversibility and performance of conversion-type materials but also the fundamental opportunity to understand the phase alteration and phase competitions in solid-solid reactions dominated by interfacial kinetics, resulting in peculiar material properties. This project will stimulate the broader materials categories to explore the influence of interfacial kinetics on phase competition and phase diagrams. The project benefits both the fundamental exploration of solid-state material chemistry and the applications for mitigating/suppressing undesirable phase transformation.

Equilibrium phase transformation and phase competition of complex systems are major subjects of materials science as the outcomes critically determined materials characteristics. However, the phase competition under conditions that deviate from equilibrium are not well studied but offer many opportunities for the exploration of a wide variety of materials properties and responses.

The objectives of the project are to understand and reveal which and how the interfacial kinetics can impose interfacial-chemical-mechanical-structural kinetic constraints to control the formation of new phases that further alter the equilibrium phase competitions between solid-solution reaction vs. solid-phase-transformation in complex conversion materials systems. Conversion materials are usually binary or ternary compounds that are promising for high lithium-ion storage capacity (3~5 times higher than the current commercial electrode materials), but the solid-state phase transformations that occur upon lithium uptake hinder high reversibility, which limits their overall application in Li-ion batteries. A new design principle of extending the reversible solid-solution (“intercalation”) phases to higher capacity by controlling the onset of solid-state phase transformation (“conversion”) via interface kinetics will be achieved to benefit the energy storage technology directly by enabling low-cost, reversible, cobalt-free, high-capacity conversion electrodes.

The scientific impacts of this project are not only the improved reversibility and performance of conversion-type materials but also the fundamental opportunity to understand the phase alteration and phase competitions in solid-solid reactions dominated by interfacial kinetics, resulting in peculiar material properties. This project will stimulate the broader materials categories to explore the influence of interfacial kinetics on phase competition and phase diagrams. The project benefits both the fundamental exploration of solid-state material chemistry and the applications for mitigating/suppressing undesirable phase transformation.