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DOE OSTI · 1883966

Structure Evolution of Chemically Degraded ZIF-8

Metz, Peter C.·Ryder, Matthew R.·Ganesan, Arvind·Bhattacharyya, Souryadeep·Purdy, Stephen C.·Nair, Sankar·Page, Katharine
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Abstract

Exposure of the metal–organic zeolitic imidazolate framework-8 (ZIF-8) to humid SO x gas cleaves Zn–N bonds, leading to framework disorder and a corresponding decrease in pore accessibility. This work shows that framework disorder exhibits a critical behavior with respect to water concentration in the gas stream. While the quantity of sulfate adsorbed at Zn nodes is at or below the detection threshold for the X-ray pair distribution function technique, precluding direct observation of the adsorbate, powder diffraction reveals clear structural alterations. Here, the onset of linker cleavage correlates to a large microstrain that diminishes as framework disorder increases. Energy-dispersive X-ray spectroscopy shows that the sulfur distribution throughout representative grains is uniform, implying the structure transformation is homogeneously nucleated and not dependent upon gas diffusion kinetics.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYDefectsGranular materialsHumidityMetal organic frameworksX-rays

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Metz, Peter C., Ryder, Matthew R., Ganesan, Arvind, Bhattacharyya, Souryadeep, Purdy, Stephen C., Nair, Sankar, Page, Katharine. 2022-06-03. Structure Evolution of Chemically Degraded ZIF-8. https://doi.org/10.1021/acs.jpcc.2c02217

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