Constructing Ultraporous Covalent Organic Frameworks in Seconds via an Organic Terracotta Process

Research
on covalent organic frameworks (COFs) has recently gathered
significant momentum by the virtue of their predictive design, controllable
porosity, and long-range ordering. However, the lack of solvent-free
and easy-to-perform synthesis processes appears to be the bottleneck
toward their greener fabrication, thereby limiting their possible
potential applications. To alleviate such shortcomings, we demonstrate
a simple route toward the rapid synthesis of highly crystalline and
ultraporous COFs in seconds using a novel salt-mediated crystallization
approach. A high degree of synthetic control in interlayer stacking
and layer planarity renders an ordered network with a surface area
as high as 3000 m2 g–1. Further, this
approach has been extrapolated for the continuous synthesis of COFs
by means of a twin screw extruder and in situ processes
of COFs into different shapes mimicking the ancient terracotta process.
Finally, the regular COF beads are shown to outperform the leading
zeolites in water sorption performance, with notably facile regeneration
ability and structural integrity.