N-doped porous carbons have been regarded as competitive candidates for CO₂ adsorption by virtue of tunable micropores and basic nitrogen sites. Herein, we synthesized the ultramicropore-enriched N-doped carbon by pyrolysis of polyethyleneimine-based polymer network which was formed by nucleophilic substitution reaction of polyethyleneimine and p-dichloroxylene. The precursor with evenly anchored amine groups on the surface and interior could not only serve as pore-forming agent by self-decomposition, but also generate abundant nitrogen sites to enhance the surface polarity. By adjusting carbonization temperatures (500, 600, 700 and 800 °C) and amounts of KOH activator, the texture properties and nitrogen contents of the N-doped porous carbons (denoted as CPDs) were tuned finely. Impressively, the CPD-600 pyrolyzed at 600 °C possessed large surface area (1638 m²/g), narrow-distributed ultramicropores (d < 0.7 nm) and high nitrogen content (6.16 wt%). The sufficient nitrogen species (especially pyrrolic-N) as the basic “CO₂-philic” sites could strengthen the affinity of polar surfaces toward CO₂ molecules. Moreover, the well-developed ultramiropores offered restricted spaces that could capture CO₂ by superposition effect of Van der Waals’ force. These advantages endowed CPD-600 with high-performance of CO₂ uptake (4.92 mmol/g), CO₂/N₂ (15/85, v/v) selectivity (31) and regenerability at 298 K and 1 bar. The rational design of polymer-derived porous carbons with tailoring structural and functional properties could be applied not only to CO₂ capture from gas mixtures but also to other advanced fields.

N掺杂的多孔碳已被视为CO _2的竞争候选物可调微孔和碱性氮位的吸附。在这里，我们通过聚乙烯亚胺和对二氯二甲苯的亲核取代反应形成的聚乙烯亚胺基聚合物网络的热解合成了超微孔富集的氮掺杂碳。在表面和内部均匀锚定胺基的前体不仅可以通过自分解充当造孔剂，而且可以生成大量的氮位以增强表面极性。通过调节碳化温度（500、600、700和800℃）和KOH活化剂的量，可以对N掺杂多孔碳（表示为CPD）的织构性质和氮含量进行微调。令人印象深刻的是，在600°C时热解的CPD-600具有较大的表面积（1638 m ²/ g），窄分布的超微孔（d <0.7 nm）和高氮含量（6.16 wt％）。作为基本的“亲₂ CO ₂ ”位的充足氮物种（尤其是吡咯N）可以增强极性表面对CO ₂分子的亲和力。此外，发达的超微孔提供了有限的空间，可以通过范德华力的叠加作用捕获CO ₂。这些优点赋予CPD-600高性能的CO ₂吸收（4.92 mmol / g），CO ₂ / N ₂（15/85，v / v）选择性（31）和在298 K和1 bar下的可再生性。具有量身定制的结构和功能特性的聚合物衍生多孔碳的合理设计不仅可以应用于一氧化碳₂从混合气体中捕获，但也捕获到其他高级领域。