Efficient in-situ conversion of low-concentration carbon dioxide in exhaust gas using silver nanoparticles in N-heterocyclic carbene polymer

Efficient utilizing CO2 is crucial approaches in achieving carbon neutralization. One of the challenges lies in the in-situ conversion of low concentration CO2 found in waste gases. This study introduces a novel heterogeneous catalyst known as silver nanoparticles in porous N-heterocyclic carbene polymer (Ag@POP-NL-3). The catalyst is synthesized via a streamlined pre-coordination method. Ag@POP-NL-3 exhibits uniform distribution of silver nanoparticles, a porous structure and nitrogen activation groups. It demonstrates high efficiency and selectivity in absorbing and activating CO2 and enabling the conversion of low concentration CO2 (30 vol%) from lime kiln waste gas into cyclic carbonate under mild conditions. This catalytic system achieves both CO2 capture and resource utilization of CO2 simultaneously, effectively fixing low-concentration CO2 from waste gases into C2+ valuable chemicals. This approach elegantly addresses two goals in one solution.