Synthesis of metal-phenanthroline-modified hypercrosslinked polymer for enhanced CO₂ capture and conversion via chemical and photocatalytic methods under ambient conditions

Catalytic conversion of CO₂ into valuable chemicals is a promising approach to mitigate the greenhouse effect and alleviate energy shortages. Hypercrosslinked polymers (HCPs) offer a scalable and stable platform for this conversion, but they often suffer from low CO₂ adsorption and activation capabilities, necessitating high temperatures and pressures for effectiveness. To overcome these limitations, nitrogen-based CO₂-philic active sites have been integrated into the structure of HCPs, enhancing CO₂ attraction and leading to superior adsorption performance. The incorporation of cobalt ions (Co²⁺) further bolsters CO₂ affinity, with HCP-PNTL-Co-B achieving the highest observed adsorption heat of 33.0 kJ mol^-1 alongside a substantial 2.0 mmol g^-1 CO₂ uptake. These modified HCPs exhibit higher yields and reaction rates in cycloaddition reactions with co-catalyst TBAB at room temperature and atmospheric pressure, while HCP-PNTL-Co-B demonstrates a higher CO production rate (2173 μmol g^-1 h^-1) and selectivity (84%) in photocatalytic reduction reaction. This research has successfully achieved outstanding carbon dioxide capture and conversion performance at room temperature and atmospheric pressure by introducing CO₂-philic active sites and cobalt ions (Co²⁺) into HCPs via facile one-step polymerization. This study provides a new approach to the design of highly efficient organic catalysts for CO₂ conversion.