Author

Rafael Gómez-Bombarelli

View on Semantic Scholar

2 papers indexed here

We haven’t gathered this author’s papers yet. Follow them and we’ll fetch their work.

Not the right person? Other researchers publish under this name.

Jul 2026

Predicting Surface Atomic Structures on Doped Perovskite Oxides Using Grand Canonical Monte Carlo: Model System of La0.6Sr0.4FeO3–δ

Surface properties of metal oxides are determined by their atomic structures, which can be exceedingly complex, including different surface terminations, chemistries and phase precipitates. First-principles studies have advanced our understanding of oxide surface reconstructions, but often face challenges due to the limited exploration of surface compositional and configurational spaces. To overcome this limitation, this study integrates bulk and surface thermodynamics consistently to effectively sample surface configurations. Our method is Grand Canonical Monte Carlo (GCMC) calculations, accelerated by a machine-learning interatomic potential. This approach is applied to a model perovskite oxide, La0.6Sr0.4FeO3–δ (LSF), a state-of-the-art oxygen electrode material for solid oxide cells. To make GCMC calculations computationally feasible, we first assessed the competing bulk phases in equilibrium with LSF. We used these phases as initial guesses at the surfaces of LSF. GCMC then refined these surface structures to identify equilibrium surface structures on LSF under different thermodynamic conditions. In calculating surface energies, the chemical potentials of the cations were evaluated as functions of the oxygen partial pressure, the bulk oxygen and cation vacancy concentrations, and the overall bulk composition. Surface segregations of SrO2, SrO, La2O3, Fe, and Ruddlesden–Popper (RP) phases were found at different oxygen chemical potentials. Surface phase diagrams of LSF (001) show that SrO-terminated RP phase segregation dominates under moderate oxygen environment, while oxidizing and reducing environments favor SrO2 formation and Fe exsolution, respectively. A decrease in temperature reduces the oxygen partial pressure window for RP segregation on the LSF (001) surface. The results provide useful insights into the surface thermodynamics of LSF (001), and the method can be leveraged to investigate surface atomic structures across a broader range of complex oxides.

M. Liu, Hao Tang, Jing Yang et al. · Chemistry of Materials · 0 citations

Review Open access Sep 2026

Designing Vanadium‐Based Oxide Electrocatalysts for Water Splitting: Experimental and Mechanistic Insights with Machine Learning

Developing efficient and durable non‐precious metal electrocatalysts for electrochemical water splitting remains a critical barrier to sustainable hydrogen production. Among earth‐abundant candidates, vanadium‐based oxide electrocatalysts are highly attractive due to their wide range of oxidation states (V 2+– V 5+ ), composition‐dependent tunability of active sites, and intrinsically flexible atomic structures. This review offers a comprehensive and mechanistic analysis of the six principal modification strategies: lattice engineering, heteroatom doping, heterojunction and interface engineering, carbon‐based hybridization, morphology engineering, and surface reconstruction and pre‐catalyst design. It highlights structure–property relationships, the identification of active sites, and operative oxygen evolution pathways. A distinctive finding across the strategies reviewed is that vanadium dissolution and surface reconstruction are design features, not degradation processes; thus, the as‐synthesized material frequently functions as a pre‐catalyst engineered to reconstruct under electrochemical operating conditions. This review further highlights how machine learning methods accelerate the atomistic modeling of structurally analogous oxide systems, offering an emerging simulation framework for addressing mechanistic questions that conventional first‐principles calculations cannot address at the scale required for this materials class. Finally, a personal perspective is offered on the challenges and future research directions for advancing vanadium‐based oxide electrocatalysts toward industrially relevant water‐splitting performance.

Y. El Issmaeli, Amina Lahrichi, Hoje Chun et al. · Advanced Functional Material... · 0 citations