CO2 Fixation and Release Mediated by Carbonate-Based Coordination Polymers

We demonstrate the synthesis of eleven carbonate (CO32−)-based coordination polymers (CPs) from CO2 and reveal the structure-property correlation of CO2 release upon decarbonation. The decarbonation temperatures (TCO2) are tunable as factors of the electronegativity of metal ions and the coordination numbers of CO32− within the CP lattices. The structural tunability of CO32−-based CPs enables high gravimetric CO2 contents (25-30 wt%) and TCO2 in the low-temperature range where low-grade waste heat can be utilized (170-230 °C). The decarbonation mechanism of CO32−-based CPs, which produces a discrete metal complex, is revealed by 3D electron diffraction and variable-temperature synchrotron X-ray diffraction. The synthetic scalability and recyclability of CO32−-based CPs render them a designable CO2 carrier.