Solvent-switchable continuous-breathing behaviour in a diamondoid metal–organic framework and its influence on CO2 versus CH4 selectivity

DOI: 10.1038/nchem.2747

Authors: Elliot J. Carrington (University of Sheffield) , Craig A. Mcanally (University of Strathclyde) , Ashleigh J. Fletcher (University of Strathclyde) , Stephen Thompson (Diamond Light Source) , Mark Warren (Diamond Light Source) , Lee Brammer (University of Sheffield)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nature Chemistry , VOL 9

State: Published (Approved)
Published: March 2017

Abstract: Understanding the behaviour of flexible metal–organic frameworks (MOFs)—porous crystalline materials that undergo a structural change upon exposure to an external stimulus—underpins their design as responsive materials for specific applications, such as gas separation, molecular sensing, catalysis and drug delivery. Reversible transformations of a MOF between open- and closed-pore forms—a behaviour known as ‘breathing’—typically occur through well-defined crystallographic transitions. By contrast, continuous breathing is rare, and detailed characterization has remained very limited. Here we report a continuous-breathing mechanism that was studied by single-crystal diffraction in a MOF with a diamondoid network, (Me2NH2)[In(ABDC)2] (ABDC, 2-aminobenzene-1,4-dicarboxylate). Desolvation of the MOF in two different solvents leads to two polymorphic activated forms with very different pore openings, markedly different gas adsorption capacities and different CO2 versus CH4 selectivities. Partial desolvation introduces a gating pressure associated with CO2 adsorption, which shows that the framework can also undergo a combination of stepped and continuous breathing.

Journal Keywords: Coordination chemistry; Crystal engineering; Metal–organic frameworks; Solid-state chemistry

Diamond Keywords: Gas Separation

Subject Areas: Chemistry, Materials


Instruments: I11-High Resolution Powder Diffraction , I19-Small Molecule Single Crystal Diffraction

Added On: 17/03/2017 16:49

Discipline Tags:

Chemistry Materials Science Chemical Engineering Engineering & Technology Metal-Organic Frameworks Metallurgy Organometallic Chemistry

Technical Tags:

Diffraction Single Crystal X-ray Diffraction (SXRD) X-ray Powder Diffraction