1 research outputs found
Microfluidic Approach toward Continuous and Ultrafast Synthesis of Metal–Organic Framework Crystals and Hetero Structures in Confined Microdroplets
Herein,
we report a novel nanoliter droplet-based microfluidic
strategy for continuous and ultrafast synthesis of metal–organic
framework (MOF) crystals and MOF heterostructures. Representative
MOF structures, such as HKUST-1, MOF-5, IRMOF-3, and UiO-66, were
synthesized within a few minutes via solvothermal reactions with substantially
faster kinetics in comparison to the conventional batch processes.
The approach was successfully extended to the preparation of a demanding
Ru<sub>3</sub>BTC<sub>2</sub> structure that requires high-pressure
hydrothermal synthesis conditions. Finally, three different types
of core–shell MOF composites, i.e., Co<sub>3</sub>BTC<sub>2</sub>@Ni<sub>3</sub>BTC<sub>2</sub>, MOF-5@diCH<sub>3</sub>-MOF-5, and
Fe<sub>3</sub>O<sub>4</sub>@ZIF-8, were synthesized by exploiting
a unique two-step integrated microfluidic synthesis scheme in a continuous-flow
mode. The synthesized MOF crystals were characterized by X-ray diffraction,
scanning electron microscopy, and BET surface area measurements. In
comparison with bare MOF-5, MOF-5@diCH<sub>3</sub>-MOF-5 showed enhanced
structural stability in the presence of moisture, and the catalytic
performance of Fe<sub>3</sub>O<sub>4</sub>@ZIF-8 was examined using
Knoevenagel condensation as a probe reaction. The microfluidic strategy
allowed continuous fabrication of high-quality MOF crystals and composites
exhibiting distinct morphological characteristics in a time-efficient
manner and represents a viable alternative to the time-consuming and
multistep MOF synthesis processes