The PdAu alloy catalyst exhibits remarkable performance in the direct synthesis of hydrogen peroxide (H₂O₂) from hydrogen and oxygen, but it still faces many challenges such as poor activity and H₂O₂ selectivity under ambient pressure as well as low utilization of precious metals. In this work, AuCu@AuPd core–shell catalysts with a Cu-enriched core and highly dispersed Pd sites on the alloy surface were successfully prepared by the simple incipient wetness impregnation method and galvanic replacement reaction. Among them, the AuCu_1.5@AuPd catalyst shows the highest H₂O₂ selectivity of 89.5% under ambient pressure. Combined with multiple characterizations and catalytic performance studies, it was proved that the highly dispersed Pd sites coordinated with Au atoms on the surface are beneficial to the synthesis of H₂O₂, while the highly dispersed Pd sites coordinated with Cu atoms show low activity for the synthesis of H₂O₂ due to the easy spillover of H* and difficulty of reaction between O₂* and H*. Since both Pd and Au atoms are located on the surface, the core–shell structure of AuCu@AuPd can improve not only the selectivity and productivity of H₂O₂ but also the utilization rate of precious metals Pd and Au.

中文翻译：

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在具有高度分散的 Pd 位点的 AuCu@AuPd 核壳催化剂上直接合成 H2O2


PdAu 合金催化剂在氢和氧直接合成过氧化氢 （H₂O₂） 方面表现出显著的性能，但仍面临许多挑战，例如在环境压力下活性差和 H₂O₂ 选择性差以及贵金属利用率低。在本工作中，通过简单的初期湿浸渍法和电偶置换反应，成功制备了具有富铜核和合金表面高度分散的 Pd 位点的AuCu@AuPd核壳催化剂。其中，AuCu_1.5@AuPd催化剂在环境压力下表现出最高的 H₂O₂ 选择性，为 89.5%。结合多重表征和催化性能研究，证明表面与Au原子配位的高分散Pd位点有利于H₂O₂的合成，而与Cu原子配位的高分散Pd位点由于H*易溢出且O₂之间反应困难，对H₂O₂的合成表现出低活性* 和 H*。由于 Pd 和 Au 原子都位于表面，因此 AuCu@AuPd 的核壳结构不仅可以提高 H₂O₂ 的选择性和生产率，还可以提高贵金属 Pd 和 Au 的利用率。