Abstract In this work, layered double hydroxides (LDHs) including the variable valence Co 2+ ions (CoAl-LDHs) is discovered to be capable of serving as the support and the reducing agent for the fabrication of well-distributed PdAu nanoparticles because of the low potential for reduction. Specifically, the active metal precursors undergo the redox process, in which Co 2+ is oxidized to Co 3+ , while active metal ions are successfully reduced to bimetallic PdAu nanoparticles with the dispersion of 73%. Furthermore, the obtained catalysts are evaluated in the selective oxidation of benzyl alcohol as the probing reaction to explore the catalytic behavior. As for intrinsic activity, PdAu/CoAl-LDHs derived by the above in situ spontaneous reduction exhibits activation energy of 62.4 kJ mol −1 , much lower than that of PdAu/CoAl-LDHs prepared by sol-immobilization. When the reaction time reaches to 4 h, the benzaldehyde selectivity over the former catalyst is up to 94%, originating from the surface electron starvation of active metals that promots the hydroxyl groups reacting with O 2 to produce benzaldehyde. Graphic Abstract

中文翻译：

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通过还原层状双氢氧化物的原位自发还原制备 Pd-Au 簇

摘要 在这项工作中，发现包含可变价 Co 2+ 离子 (CoAl-LDHs) 的层状双氢氧化物 (LDHs) 能够作为载体和还原剂用于制备分布均匀的 PdAu 纳米粒子，因为减少的可能性低。具体而言，活性金属前驱体经历氧化还原过程，其中 Co 2+ 被氧化为 Co 3+ ，而活性金属离子成功还原为双金属 PdAu 纳米颗粒，分散度为 73%。此外，所获得的催化剂在苯甲醇的选择性氧化中作为探测反应进行了评估，以探索其催化行为。至于本征活性，通过上述原位自发还原得到的 PdAu/CoAl-LDHs 表现出 62.4 kJ mol -1 的活化能，远低于通过溶胶固定制备的 PdAu/CoAl-LDHs。当反应时间达到 4 h 时，苯甲醛选择性比前一种催化剂高达 94%，这源于活性金属的表面电子饥饿促进羟基与 O 2 反应生成苯甲醛。图形摘要