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DOE OSTI · 3797992

Cryogenic Reduction of Surface-Bound HKUST-1Crystallites

Hu, Tianhao·Head, Ashley R. (ORCID:0000000187330165)·Lee, Dennis T.·Nykypanchuk, Dmytro·Tong, Xiao·Stacchiola, Dario
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Abstract

HKUST-1 is a canonical Cu-based metal-organic framework (MOF) with potential roles in catalysis. A convenient hydroxy double salt templating synthesis was used to produce a thin layer of HKUST-1 crystallites amenable to surface science spec-troscopies under controlled conditions. To study the nature of the Cu sites, N2 and CO2 were adsorbed at cryogenic tempera-tures as passive probe molecules for Cu2+ sites. CO, which is commonly used as a probe molecule of both Cu2+ and Cu1+ sites in porous materials, was found to be a non-innocent probe molecule that reduces the Cu2+ and forms CO2. Isotopically labeled 13CO confirmed the Cu2+ reduction and CO oxidation. The results offer a way to tune Cu oxidation states in HKUST-1, even in the cryogenic temperature regime.

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Hu, Tianhao, Head, Ashley R. (ORCID:0000000187330165), Lee, Dennis T., Nykypanchuk, Dmytro, Tong, Xiao, Stacchiola, Dario. 2026-08-25. Cryogenic Reduction of Surface-Bound HKUST-1Crystallites. https://doi.org/10.1021/acs.jpcc.6c02368

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