Platinum (Pt) oxides are vital catalysts in numerous reactions, but research indicates that they decompose at high temperatures, limiting their use in high-temperature applications. In this study, we identify a two-dimensional (2D) crystalline Pt oxide with remarkable thermal stability (1,200 K under nitrogen dioxide) using a suite of in situ methods. This 2D Pt oxide, characterized by a honeycomb lattice of Pt atoms encased between dual oxygen layers forming a six-pointed star structure, exhibits minimized in-plane stress and enhanced vertical bonding due to its unique structure, as revealed by theoretical simulations. These features contribute to its high thermal stability. Multiscale in situ observations trace the formation of this 2D Pt oxide from α-PtO₂, providing insights into its formation mechanism from the atomic to the millimetre scale. This 2D Pt oxide with outstanding thermal stability and distinct surface electronic structure subverts the previously held notion that Pt oxides do not exist at high temperatures and can also present unique catalytic capabilities. This work expands our understanding of Pt oxidation species and sheds light on the oxidative and catalytic behaviours of Pt oxide in high-temperature settings.

铂 (Pt) 氧化物是许多反应中的重要催化剂，但研究表明它们在高温下会分解，限制了它们在高温应用中的使用。在这项研究中，我们使用一套原位方法鉴定了一种具有出色热稳定性（二氧化氮下 1,200 K）的二维 (2D) 结晶 Pt 氧化物。理论模拟显示，这种二维 Pt 氧化物的特点是 Pt 原子蜂窝状晶格包裹在双氧层之间，形成六角星形结构，由于其独特的结构，其面内应力最小化，垂直键合增强。这些特性有助于其高热稳定性。多尺度原位观测追踪了这种由 α-PtO ₂形成的二维 Pt 氧化物，提供了从原子到毫米尺度的形成机制的见解。这种二维铂氧化物具有出色的热稳定性和独特的表面电子结构，颠覆了之前铂氧化物在高温下不存在的观念，并且还可以呈现独特的催化能力。这项工作扩大了我们对 Pt 氧化物的理解，并揭示了 Pt 氧化物在高温环境下的氧化和催化行为。