posted on 2023-01-30, 06:43authored bySoyeon Ko, UnJin Ryu, Hyunjin Park, Alejandro M. Fracaroli, WooYeon Moon, Kyung Min Choi
The uniqueness of multivariate metal–organic
frameworks
(MTV-MOFs) has been widely explored to discover their unknown opportunities.
While mesoscopic apportionments have been studied, macroscopic heterogeneity
and its spatial effects remain unexplored in MTV-MOFs. In this study,
we investigated the effect of macroscopic heterogeneity on MTV-MOFs
on their uptake behaviors by comparing three types of MTV-MOFs having
the functional groups in inner, outer, or entire parts of crystals.
Their adsorption behavior for carbon dioxide (CO2) and
water (H2O) brought out that functional groups located
in the outer part of the crystals dominantly influence the sorption
behavior of MTV-MOFs. These results are also visualized by observing
iodine adsorption in the three types of MTV-MOFs using scanning transmission
electron microscopy–electron energy loss spectroscopy. We believe
that this finding provides new ways to decipher and design MTV-MOFs
for their unusual properties.