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Updated: May 28, 2026
Microfluidic-based Synthesis of Covalent Organic Frameworks (COFs): A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface
Published on: July 10, 2017
A 2D covalent organic framework with 4.7-nm pores and insight into its interlayer stacking
Eric L Spitler1, Brian T Koo, Jennifer L Novotney
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.
Abstract:
Two-dimensional layered covalent organic frameworks (2D COFs) organize π-electron systems into ordered structures ideal for exciton and charge transport and exhibit permanent porosity available for subsequent functionalization. A 2D COF with the largest pores reported to date was synthesized by condensing 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) and 4,4'-diphenylbutadiynebis(boronic acid) (DPB). The COF was prepared as both a high surface area microcrystalline powder as well as a vertically oriented thin film on a transparent single-layer graphene/fused silica substrate. Complementary molecular dynamics and density functional theory calculations provide insight into the interlayer spacing of the COF and suggest that adjacent layers are horizontally offset by 1.7-1.8 Å, in contrast to the eclipsed AA stacking typically proposed for these materials.
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