A Fine-Tuned
Fluorinated MOF Addresses the Needs for
Trace CO<sub>2</sub> Removal and Air Capture Using Physisorption
Prashant
M. Bhatt
Youssef Belmabkhout
Amandine Cadiau
Karim Adil
Osama Shekhah
Aleksander Shkurenko
Leonard J. Barbour
Mohamed Eddaoudi
10.1021/jacs.6b05345.s001
https://acs.figshare.com/articles/journal_contribution/A_Fine-Tuned_Fluorinated_MOF_Addresses_the_Needs_for_Trace_CO_sub_2_sub_Removal_and_Air_Capture_Using_Physisorption/3491150
The
development of functional solid-state materials for carbon
capture at low carbon dioxide (CO<sub>2</sub>) concentrations, namely,
from confined spaces (<0.5%) and in particular from air (400 ppm),
is of prime importance with respect to energy and environment sustainability.
Herein, we report the deliberate construction of a hydrolytically
stable fluorinated metal–organic framework (MOF), <b>NbOFFIVE</b>-1-Ni, with the appropriate pore system (size, shape, and functionality),
ideal for the effective and energy-efficient removal of trace carbon
dioxide. Markedly, the CO<sub>2</sub>-selective <b>NbOFFIVE</b>-1-Ni exhibits the highest CO<sub>2</sub> gravimetric and volumetric
uptake (ca. 1.3 mmol/g and 51.4 cm<sup>3</sup> (STP) cm<sup>–3</sup>) for a physical adsorbent at 400 ppm of CO<sub>2</sub> and 298 K.
Practically, <b>NbOFFIVE</b>-1-Ni offers the complete CO<sub>2</sub> desorption at 328 K under vacuum with an associated moderate
energy input of 54 kJ/mol, typical for the full CO<sub>2</sub> desorption
in conventional physical adsorbents but considerably lower than chemical
sorbents. Noticeably, the contracted square-like channels, affording
the close proximity of the fluorine centers, permitted the enhancement
of the CO<sub>2</sub>–framework interactions and subsequently
the attainment of an unprecedented CO<sub>2</sub> selectivity at very
low CO<sub>2</sub> concentrations. The precise localization of the
adsorbed CO<sub>2</sub> at the vicinity of the periodically aligned
fluorine centers, promoting the selective adsorption of CO<sub>2</sub>, is evidenced by the single-crystal X-ray diffraction study on <b>NbOFFIVE</b>-1-Ni hosting CO<sub>2</sub> molecules. Cyclic CO<sub>2</sub>/N<sub>2</sub> mixed-gas column breakthrough experiments under
dry and humid conditions corroborate the excellent CO<sub>2</sub> selectivity
under practical carbon capture conditions. Pertinently, the notable
hydrolytic stability positions <b>NbOFFIVE</b>-1-Ni as the new
benchmark adsorbent for direct air capture and CO<sub>2</sub> removal
from confined spaces.
2016-07-08 00:00:00
fluorine centers
CO 2 gravimetric
CO 2 molecules
CO 2
CO 2 desorption
Trace CO 2 Removal
51.4 cm 3
CO 2 selectivity
CO 2 removal
trace carbon dioxide
CO 2 concentrations
STP
MOF