Novel Hierarchical Meso-Microporous Hydrogen-Bonded Organic Framework for Selective Separation of Acetylene and Ethylene versus Methane

Herein
we construct a novel three-dimension (3D) hydrogen-bonded
organic framework (PFC-2) with a hierarchical meso-microporous structure,
which possesses the largest open channels relative to all known HOFs
and exhibits highly selective separation of acetylene and ethylene
versus methane at ambient atmosphere. Comparison on the adsorption
behaviors of PFC-2 and an analogue structure PFC-1 clearly shows that
the extensively existed unpaired hydrogen bond acceptor CO
groups in PFC-2 dramatically increase the affinity between gas molecules
and frameworks, resulting in high isosteric heats of adsorption (Qst) and better selectivity toward C2 hydrocarbons to methane. The study presented here demonstrated an
effective strategy to optimize gas adsorption/separation performance
of HOF materials.