Microstructure evolution and kinetics of B-site nanoparticle exsolution from an A-site-deficient perovskite surface: a phase-field modeling and simulation study.

Segregation-exsolution of B-site catalytic dopants as nanoparticles from A-site-deficient perovskite (A1-xBO3-δ) surfaces has been actively used in recent years to promote the activity and durability of perovskite oxides towards efficient fuel oxidation and water splitting. The mechanistic understandings are currently gained from equilibrium thermodynamics, such as atomic scale density functional theory calculations, in terms of segregation energy, interaction energy and elastic energy. Herein, we have developed a micro-scale phase-field model framework that describes the kinetics and microstructure evolutions of the B-site segregation and nanoparticle exsolution from the A1-xBO3-δ surface.