Sintering-induced aggregation of active metals is a major cause of catalyst deactivation. Catalysts that can operate above 800°C are rare. Here, we report an unusual noble metal catalyst with sintering-induced activation at temperatures up to 1,000°C. The catalyst consists of atomically dispersed palladium embedded in a reducible SnO₂ support designated for lean methane combustion. High temperature reaction simultaneously causes favorable changes of palladium ensemble state combining synergistically with lattice oxygen activation. Such changes lead to at least one order of magnitude improvement of the intrinsic reactivity, which compensates the surface area loss. Extensive characterizations such as atom probe tomography, X-ray absorption spectroscopy, and isotope tracking together with theoretical calculations illustrate the structure and surface chemistry changes and their impacts on the reaction mechanism. The catalyst also shows notable long-term stability and facile regeneration after poisoning. Our work may provide new insights into designing active and thermally stable catalysts.

烧结引起的活性金属聚集是催化剂失活的主要原因。可在800°C以上操作的催化剂很少。在这里，我们报告了一种不寻常的贵金属催化剂，其在高达1,000°C的温度下具有烧结诱导的活化作用。催化剂由嵌入可还原SnO _2中的原子分散钯组成指定用于稀薄甲烷燃烧的支架。高温反应同时引起钯集合态的有利变化，与晶格氧活化作用协同作用。这种变化导致固有反应性提高至少一个数量级，这补偿了表面积损失。诸如原子探针层析成像，X射线吸收光谱和同位素跟踪等广泛的表征以及理论计算，说明了结构和表面化学变化及其对反应机理的影响。该催化剂在中毒后还显示出显着的长期稳定性和容易的再生。我们的工作可能会为设计活性和热稳定的催化剂提供新的见解。