A Sequential One‐Pot Block Copolymer Synthesis: Toward Mesoporous Carbon Materials for Selective CO$_2$ Adsorption

Polymer-derived porous carbon nanomaterials are pivotal for addressing global challenges, particularly in energy storage as well as carbon capture, utilization, and storage (CCUS). Herein, we report a facile one-pot synthetic route to block copolymer (BCP) precursors for mesoporous carbons using a photo-iniferter reversible addition-fragmentation chain transfer (PI-RAFT) polymerization. This scalable approach yields well-defined polyacrylonitrile-block-poly(acrylonitrile-co-n-butyl acrylate) (PAN-b-P(AN-co-BA)) block copolymers with molecular weights up to 286 kg mol$^{−1}$, alongside other common PAN BCPs. The characteristics of the BCPs are confirmed exemplary for PAN$_{209}$-b-P(AN$_{207}$-co-BA$_{149}$)$^{41.2}$ by differential scanning calorimetry, evidenced by two glass transition temperatures (91.5 °C and −13.7 °C) and by atomic force microscopy, which confirmed distinct phase separation of thin films. Also, the robustness of the polymerization was demonstrated by synthesizing multiple sets of BCPs and a numbering-up experiment with 10 samples, showing an average size of 49.8 ± 2.3 kg mol$^{−1}$ with a dispersity Đ of 1.22 ± 0.01. Subsequent electrospinning and carbonization transformed BCP into a nitrogen-doped (11 at.%) hierarchical porous carbon membrane. This membrane exhibited promising CCUS performance, characterized by high CO$_2$ adsorption capacity (2.52 mmol g$^{−1}$), rapid desorption kinetics, and high selectivity over N$_2$. This work establishes a streamlined platform to produce functional carbon architectures for environmental remediation.