• Farha, Omar K.
• Lercher, Johannes A.
• Zheng, Jian
• Camaioni, Donald M.
• Sanchez-Sanchez, Maricruz
• Gagliardi, Laura
• Vjunov, Aleksei
• Fulton, John L.
• Ikuno, Takaaki
• Pahls, Dale R.
• Browning, Nigel D.
• Ortuño, Manuel A.
• Ray, Debmalya
• Mehdi, B. Layla
• Li, Zhanyong
• Hupp, Joseph T.

Abstract

<p>Copper oxide clusters synthesized via atomic layer deposition on the nodes of the metal-organic framework (MOF) NU-1000 are active for oxidation of methane to methanol under mild reaction conditions. Analysis of chemical reactivity, in situ X-ray absorption spectroscopy, and density functional theory calculations are used to determine structure/activity relations in the Cu-NU-1000 catalytic system. The Cu-loaded MOF contained Cu-oxo clusters of a few Cu atoms. The Cu was present under ambient conditions as a mixture of ∼15% Cu⁺ and ∼85% Cu²⁺. The oxidation of methane on Cu-NU-1000 was accompanied by the reduction of 9% of the Cu in the catalyst from Cu²⁺ to Cu⁺. The products, methanol, dimethyl ether, and CO₂, were desorbed with the passage of 10% water/He at 135 °C, giving a carbon selectivity for methane to methanol of 45-60%. Cu oxo clusters stabilized in NU-1000 provide an active, first generation MOF-based, selective methane oxidation catalyst.</p>

Topics

• density
• cluster
• Carbon
• theory
• copper
• density functional theory
• x-ray absorption spectroscopy
• atomic layer deposition