Synthesis of 2D Metal–Organic Nanosheets (MONs) by Liquid Phase Exfoliation: Applications in Effective Delivery of Antiulcer Drugs and Selective Adsorption and Removal of Cationic Dyes

Nowadays, the fabrication of 2D metal–organic
nanosheets
(2D MONs) has entered the research arena fascinating researchers worldwide.
However, a lack of efficient and facile methods has remained a bottleneck
for the manufacturing of these 2D MONs. Herein, a 2D metal–organic
framework (MOF), i.e., 2D Cu-MOF, was synthesized using a facile and
convenient stirring method by using 4,4′-trimethylenedipyridine
(TMDP) as an organic linker. The as-prepared MOF was characterized
in detail and based on single crystal X-ray diffraction analysis,
it was established that tangled layers in the 2D Cu-MOF are interconnected
to produce thick strands. These tangled layers could be easily separated
via ultrasonication-induced liquid phase exfoliation (UILPE) to give
the 2D Cu-MON as illustrated through Tyndall light scattering and
exhaustive microscopic exploration such as scanning electron microscopy
(SEM) and transmission electron microscopy (TEM). The application
of this 2D Cu-MON was assessed in the field of drug delivery revealing
exceptional drug loading for the drug lansoprazole (LPZ) by 2D Cu-MONs
as well as drug release in the acidic and neutral medium demonstrating
that the 2D Cu-MON is an excellent carrier for antiulcer drug delivery.
For environmental protection, the application of 2D Cu-MON was also
examined toward the removal of various cationic and anionic dyes with
excellent selectivity toward cationic dye removal. The plausible mechanism
for dye removal indicated the involvement of cation−π
and π–π interactions, for the effective adsorption
of cationic dyes as well as a increase in the surface area of 2D Cu-MON
by UILPE. Remarkably, the high drug loading and dye removal are imputed
to the increase in surface area by UILPE. In a nutshell, the developed
2D Cu-MON will prove to be beneficial for application in the field
of drug delivery as well as for wastewater treatment.