Abstract A highly active palladium catalyst supported on SiO2-modified cobalt-nickel mixed oxide (denoted as 0.5Pd/M-Co1Ni4) was prepared and used for lean methane combustion. It was found that such a surface modification strategy enhanced the synergistic interaction between deposited palladium phase and reactive cobalt-nickel oxide, leading to substantial improvement in performance towards methane combustion. Over 0.5Pd/M-Co1Ni4, 90% methane conversion was realized at 323℃ and a space velocity of 60,000 mLg−1 h−1, which is 62 °C lower than that required for its untreated counterpart, 0.5Pd/Co1Ni4. The results of XRD, TEM, transmission FTIR and XPS demonstrated that the introduced SiO2, which was presented as an amorphous phase covering the carrier surface, could effectively tune the electronic structure of both Co1Ni4 support and palladium entities. More importantly, H2-TPR and O2-TPD results of 0.5Pd/M-Co1Ni4 revealed that the presence of SiO2 could enhance the low-temperature redox capability and increase the supply of oxygen species during the reaction process. We believe that the combination of PdOx (1

中文翻译：

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表面改性钴镍混合氧化物负载高活性钯催化剂用于贫甲烷低温氧化

摘要 制备了一种负载在SiO2 改性钴镍混合氧化物（记为0.5Pd/M-Co1Ni4）上的高活性钯催化剂，用于贫甲烷燃烧。发现这种表面改性策略增强了沉积的钯相和活性钴镍氧化物之间的协同相互作用，从而显着提高了对甲烷燃烧的性能。超过 0.5Pd/M-Co1Ni4，在 323℃和 60,000 mLg-1 h-1 的空速下实现了 90% 的甲烷转化率，比未处理的对应物 0.5Pd/Co1Ni4 所需的空速低 62°C。XRD、TEM、透射 FTIR 和 XPS 的结果表明，引入的 SiO2 表现为覆盖载体表面的无定形相，可以有效地调整 Co1Ni4 载体和钯实体的电子结构。更重要的是，0.5Pd/M-Co1Ni4 的 H2-TPR 和 O2-TPD 结果表明，SiO2 的存在可以提高反应过程中的低温氧化还原能力并增加氧物种的供应。我们认为 PdOx (1