Controlled synthesis of efficient CO2 adsorbents with high porosities and CO2 binding affinities remains a challenge. Herein, we report the use of a substituent effect to develop a novel family of porous organic polymers for enhanced carbon capture. Based on the in silico-aided design strategy, the task-specific polymeric adsorbent derived from a 2,6-carbazole-substituted pyridinic scaffold exhibits a superior uptake of CO2, which reaches as high as 5.76 mmol g 1at 273 K and 1 bar and ranks among the best by porous polymeric CO2 adsorbents. This approach not only enables us to achieve a very high CO2 capture for porous polymers but also provides tunable control of polymeric architectures and, in turn, their properties.