Stability of Zeolitic Imidazolate Frameworks in NO2

• DOI: 10.1021/acs.jpcc.8b11377
• Publication Date: 2019-01-04T11:52:01Z
• Authors: Souryadeep Bhatta...; Rebecca Han; Jayraj N. Joshi; Guanghui Zhu; Ryan P. Lively; Krista S. Walton; David S. Sholl; Sankar Nair
• Keywords: Zeolitic imidazolate framework; Nanoporous

The use of nanoporous zeolitic imidazolate frameworks (ZIFs) in separation processes is attractive, but the presence acid gases such as SOx or NOx process streams can have detrimental effects. While we recently developed a mechanistic picture SOx–ZIF interactions, here describe remarkably different effects NO2 on ZIFs. ZIFs with representative range stabilities are all unstable—as defined by loss crystallinity and porosity—in dry humid NO2, whereas most stable some even SOx. A detailed mechanism based Fourier transform infrared spectroscopy density functional theory calculations. H-abstraction free radical subsequent acidic species formation major degradation pathways, while adsorbed HNO3 conditions an additional pathway hydrophilic These findings strongly suggest that new strategies to stabilize ZIFs/metal–organic toward attack required.