Title: Precise Control of Molecular Self‐Diffusion in Isoreticular and Multivariate Metal‐Organic Frameworks

Abstract

Understanding the factors that affect self-diffusion in isoreticular and multivariate (MTV) MOFs is key to their application in drug delivery, separations, and heterogeneous catalysis. Here, we measure the apparent self-diffusion of solvents saturated within the pores of large single crystals of MOF-5, IRMOF-3 (amino-functionalized MOF-5), and 17 MTV-MOF-5/IRMOF-3 materials at various mole fractions. We find that the apparent self-diffusion coefficient of N,N-dimethylformamide (DMF) may be tuned linearly between the diffusion coefficients of MOF-5 and IRMOF-3 as a function of the linker mole fraction. We compare a series of solvents at saturation in MOF-5 and IRMOF-3 to elucidate the mechanism by which the linker amino groups tune molecular diffusion. The ratio of the self-diffusion coefficients for solvents in MOF-5 to those in IRMOF-3 is similar across all solvents tested, regardless of solvent polarity. We conclude that average pore aperture, not solvent-linker chemical interactions, is the primary factor responsible for the different diffusion dynamics upon introduction of an amino group to the linker.

Authors:

Osborn Popp, Thomas M. ^[1]; Plantz, Ariel Z. ^[2]; Yaghi, Omar M. ^[3]; Reimer, Jeffrey A. ^[4]

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+ Show Author Affiliations

1. Department of Chemistry, Kavli Energy NanoSciences Institute at Berkeley, and Berkeley Global Science InstituteUniversity of California-Berkeley Berkeley, California 94720 USA, Department of Chemical and Biomolecular EngineeringUniversity of California-Berkeley Berkeley, California 94720 USA, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley Berkeley CA 94720 USA
2. Department of Chemical and Biomolecular EngineeringUniversity of California-Berkeley Berkeley, California 94720 USA
3. Department of Chemistry, Kavli Energy NanoSciences Institute at Berkeley, and Berkeley Global Science InstituteUniversity of California-Berkeley Berkeley, California 94720 USA, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley Berkeley CA 94720 USA
4. Department of Chemical and Biomolecular EngineeringUniversity of California-Berkeley Berkeley, California 94720 USA, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley Berkeley CA 94720 USA

Publication Date:

2019-12-12

Research Org.:

Energy Frontier Research Centers (EFRC) (United States). Center for Gas Separations Relevant to Clean Energy Technologies (CGS); Univ. of California, Oakland, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1591981

Alternate Identifier(s):

OSTI ID: 1591982; OSTI ID: 1623520; OSTI ID: 1760198

Grant/Contract Number:  

SC0001015; AC02-05CH11231

Resource Type:

Published Article

Journal Name:

ChemPhysChem

Additional Journal Information:

Journal Name: ChemPhysChem Journal Volume: 21 Journal Issue: 1; Journal ID: ISSN 1439-4235

Publisher:

ChemPubSoc Europe

Country of Publication:

Germany

Language:

English

Subject:

diffusion; liquids; metal-organic frameworks; nuclear magnetic resonance; pulsed-field gradient; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY