Abstract:
The development of efficient heterogeneous catalysts suitable for carbon capture and utilization (CCU) under
mild conditions is a promising step towards mitigating the
growing concentration of CO2
in the atmosphere. Herein, we
report the construction of a hydrogen-bonded 3D framework, {[Zn(hfipbba)(MA)]·3DMF}n
(hfipbba=4,4’-(hexaflouroisopropylene)bis(benzoic acid)) (HbMOF1) utilizing Zn
II
center, a partially fluorinated, long-chain dicarboxylate
ligand (hfipbba), and an amine-rich melamine (MA) coligand. Interestingly, the framework possesses two types of
1D channels decorated with CO2
-philic (@NH2 and @CF3
)
groups that promote the highly selective CO2 adsorption by
the framework, which was supported by computational simulations. Further, the synergistic involvement of both Lewis
acidic and basic sites exposed in the confined 1D channels
along with high thermal and chemical stability rendered
HbMOF1 a good heterogeneous catalyst for the highly efficient fixation of CO2
in a reaction with terminal/internal epoxides at mild conditions (RT and 1 bar CO2
). Moreover, indepth theoretical studies were carried out using periodic
DFT to obtain the relative energies for each stage involved
in the catalytic reaction and an insight mechanistic details of
the reaction is presented. Overall, this work represents a rare
demonstration of rational design of a porous Zn
II MOF incorporating multiple functional sites suitable for highly efficient
fixation of CO2 with terminal/internal epoxides at mild conditions supported by comprehensive theoretical studies.
