Abstract
Metal-organic frameworks (MOFs) have great potential for the capture of
volatile iodine. The effect of a precise regulation of active sites in
JLNU-4 (MOFs) on capture of iodine was investigated by Monte Carlo (MC)
method and molecular dynamics (MD), and it was found that the larger the
Zn/Cd atomic ratio, the better the iodine capture. Interestingly,
compared with the meta-position regulation of Zn/Cd, the ortho-positions
regulation increased the free volume of the crystal and enhanced the
interaction between Cd and I, thus improving the capture capacity of
iodine. The first-principles study revealed the charge transfer of each
atom in the MOFs crystal with I2 during iodine capture and the secondary
bonds with weak covalent interactions were all formed after I2
adsorption onto MOFs. These findings provide a reference for the capture
of radioactive iodine and a theoretical basis for the strategies for
precise regulation of MOFs in the future.