Research Progress on the Preparation of Porous Polymers and Their Carbon Dioxide Capture and Conversion Performance

ABSTRACT: The increasing atmospheric concentration of CO₂ has stimulated intensive research into materials that can capture, separate, and utilize CO₂ efficiently. Porous organic polymers (POPs) are attractive platforms because their molecular building blocks, pore structures, and surface functionalities can be tailored over a wide range while maintaining good chemical and thermal stability. Beyond equilibrium adsorption, POPs can be integrated into mixed-matrix and thin-film membranes for CO₂ separation, or engineered with basic/ionic/metal sites to combine CO₂ enrichment with catalytic conversion. This review summarizes representative synthesis strategies for hypercrosslinked polymers (HCPs), conjugated microporous polymers (CMPs), polymers of intrinsic microporosity (PIMs), porous aromatic frameworks (PAFs), covalent organic frameworks (COFs), and covalent triazine frameworks (CTFs). It critically discusses how pore size, ultramicropore fraction, framework polarity, nitrogen content, accessible active sites, and structural order affect CO₂ capture and separation. Recent progress in capture-integrated CO₂ conversion is also highlighted, together with the remaining challenges in data comparability, membrane defects, scale-up, regeneration energy, and structure-property optimization.