Rational Construction of a Responsive Azo-Functionalized Porous Organic Framework for CO(2) Sorption

An azo-functionalized porous organic framework (denoted as JJU-1) was synthesized via FeCl(3)-promoted oxidative coupling polymerization. By virtue of a porous skeleton and a light/heat responsive azo functional group, this task-specific JJU-1 displays a reversible stimuli-responsive adsorption property triggered by UV irradiation and heat treatment. The initial Brunauer–Emmet–Teller (BET) surface area of this porous material is 467 m(2) g(–1). The CO(2) sorption isotherms exhibit a slight decrease after UV irradiation because of the trans to cis conversion of the azo functional skeleton. It is worth mentioning that the responsive CO(2) adsorption performance can be recycled for three cycles via alternating external stimuli, confirming the excellently reversible switchability of trans-to-cis isomerization and controllable CO(2) adsorption.