Zirconium metal–organic cage decorated with squaramides imparts dual activation for chemical fixation of CO2 under mild conditions.

A "two-in-one" dual activation strategy has been developed to give high-density hydrogen-bonding (HB) active units and Lewis acid (LA) active centres by immobilizing squaramides into metal–organic cages (MOCs). The obtained MOC served as an efficient catalyst for the chemical fixation of CO₂ under mild conditions up to 99% yields with good recyclability, and the mechanism of high catalytic activity has been further explored. [ABSTRACT FROM AUTHOR]