Solid oxide proton conductor materials are crucial for enabling hydrogen-based energy applications such as solid oxide fuel cells and solid oxide membranes. The improvement in the performance and efficiency of these applications requires the development of novel solid oxide proton conductor materials with higher proton conduction. Recently, brownmillerite Sr₂Co₂O₅ (also known as SrCoO_2.5) was reported to exhibit exceptionally high proton conductivity at lower temperatures (40–140 °C) compared to typical perovskite-based oxide proton conductors. In this study, we perform first-principles calculations to reveal the atomistic mechanisms of proton insertion and diffusion in this brownmillerite structure. By studying hydrogenated brownmillerite Sr₂Co₂O₅ in a range of H concentrations, we reveal the diffusion mechanisms in brownmillerite, which give rise to faster proton diffusion than in perovskite proton conductors. The understanding of fast proton conduction mechanisms in brownmillerite provides insight into the future development and discovery of novel proton conductor materials.

中文翻译：

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褐铁矿Sr ₂ Co ₂ O _5中质子快速扩散的计算研究

固体氧化物质子导体材料对于实现基于氢的能源应用（例如固体氧化物燃料电池和固体氧化物膜）至关重要。这些应用的性能和效率的提高要求开发具有更高质子传导性的新型固体氧化物质子导体材料。最近，褐铁矿Sr ₂ Co ₂ O ₅（也称为SrCoO _2.5与典型的基于钙钛矿的氧化物质子导体相比，据报道在较低的温度（40–140°C）下，它具有极高的质子传导性。在这项研究中，我们进行第一性原理计算，以揭示质子插入和扩散在这种棕色镁橄榄石结构中的原子机理。通过研究在一定H浓度范围内的氢化褐煤Sr ₂ Co ₂ O ₅，我们揭示了褐煤中的扩散机理，与钙钛矿质子导体相比，质子的扩散速度更快。对褐闪石中快速质子传导机理的理解为新型质子导体材料的未来发展和发现提供了见识。