Supported single-atoms and sub-nanometre clusters have exhibited superb catalytic performance toward many reactions. However, inactivation of single-atom or cluster catalysts in complex reactive conditions poses major challenge for their practical application. Herein, we demonstrate that the prepared Pd-UiO-66 with ultra-low Pd loading (0.05 wt%) contains three robust active Pd species, (isolated Pd atom (Pd₁), sub-nanometre Pd clusters (Pd_c) and Pd nanoparticles (Pd_n)) and presents superb activity for toluene oxidation and water resistance (10.0 vol%). Experiments and theoretical calculations firstly confirm that consecutive H₂-O₂ and reaction gas treatment (1000 ppm toluene in 20 vol.%O₂/Ar) induce residual N species from solvent N, N-dimethylformamide to enter UiO-66 skeleton forming Pd₁-N₁ structures. DFT calculations reveal that the synergistic effect of Pd species (namely, the enhanced activation of O₂ and H₂O by Pd₁ and the improved adsorption of toluene by Pd_c and Pd_n) is the main factor for the excellent activity of Pd-U-H-O-reused catalyst.

支持的单原子和亚纳米簇对许多反应都表现出极好的催化性能。然而，在复杂的反应条件下单原子或簇催化剂的失活对其实际应用提出了重大挑战。在此，我们证明了制备的 Pd-UiO-66 具有超低 Pd 负载量（0.05 wt%），包含三种稳健的活性 Pd 物质（孤立的 Pd 原子 (Pd ₁ )、亚纳米 Pd 簇 (Pd _c ) 和 Pd纳米粒子 (Pd _n )) 并表现出极好的甲苯氧化活性和耐水性 (10.0 vol%)。实验和理论计算首先证实了连续的 H ₂ -O ₂和反应气体处理（1000 ppm 甲苯在 20 vol.%O ₂/Ar) 诱导溶剂 N，N-二甲基甲酰胺中残留的 N 物质进入 UiO-66 骨架，形成 Pd ₁ -N ₁结构。DFT计算表明，Pd物种的协同效应（即Pd _{1对O 2}和H ₂ O的增强活化以及Pd _c和Pd _n对甲苯吸附的改善）是Pd-活性优异的主要因素。 UHO重复使用的催化剂。