New highly oxygen-active materials may enhance many energy-related technologies by enabling efficient oxygen-ion transport at lower temperatures, for example, below ~400 °C. Interstitial oxygen conductors have the potential to realize such performance but have received far less attention than vacancy-mediated conductors. Here we combine physically motivated structure and property descriptors, ab initio simulations and experiments to demonstrate an approach to discover new fast interstitial oxygen conductors. Multiple new families were found, which adopt completely different structures from known oxygen conductors. From these families, we synthesized and studied oxygen kinetics in La₄Mn₅Si₄O_22+δ, a representative member of the perrierite/chevkinite family. We found that La₄Mn₅Si₄O_22+δ has higher oxygen-ion conductivity than the widely used yttria-stabilized ZrO₂, and among the highest surface oxygen exchange rates at the intermediate temperature of known materials. The fast oxygen kinetics is the result of simultaneously active interstitial and interstitialcy diffusion pathways. We propose that the essential features for forming an effective interstitial oxygen conductor are the availability of electrons and structural flexibility, enabling a sufficient accessible volume. This work provides a powerful approach for understanding and discovering new interstitial oxygen conductors.

新型高氧活性材料可以通过在较低温度（例如低于约400°C）下实现有效的氧离子传输来增强许多能源相关技术。间隙氧导体有潜力实现这种性能，但受到的关注远远少于空位介导的导体。在这里，我们结合物理驱动的结构和属性描述符、从头算模拟和实验来演示一种发现新的快速间隙氧导体的方法。发现了多个新家族，它们采用与已知氧导体完全不同的结构。从这些家族中，我们合成并研究了橄榄岩的代表性成员La ₄ Mn ₅ Si ₄ O _22+δ 中的氧动力学/chevkinite 家族。我们发现 La ₄ Mn ₅ Si ₄ O _22+δ 比广泛使用的氧化钇稳定 ZrO < 具有更高的氧离子电导率b8>，在已知材料的中间温度下表面氧交换率最高。快速的氧动力学是同时活跃的间隙和间隙扩散路径的结果。我们认为形成有效间隙氧导体的基本特征是电子的可用性和结构灵活性，从而实现足够的可接近体积。这项工作为理解和发现新的间隙氧导体提供了一种强大的方法。