Reversible adsorption and sieving of trace <scp>NH₃</scp> from <scp>NH₃</scp>‐<scp>H₂</scp> fuel cells systems using sulfonated porous polydivinylbenzene

Abstract Trace ammonia reversible adsorption and sieving using solid adsorbents present a critical challenge in the practical deployment of ammonia‐hydrogen fuel cells. Herein, we design porous polydivinylbenzene (P‐PDVB) through one‐pot solvothermal polymerization without additional templates. Subsequently, solvent‐induced network swelling was performed to achieve deep sulfonation of the P‐PDVB using chlorosulfonic acid, resulting in P‐PDVB‐SO 3 H‐x, which possess large specific surface areas, abundant micro‐mesoporosity, and high acid site densities. Notably, P‐PDVB‐SO 3 H‐x demonstrate superior performance for the selective capture and sieving of NH 3 from an N 2 /H 2 /NH 3 mixture, outperforming most previously reported NH 3 adsorbents. Thus, P‐PDVB‐SO 3 H‐x can serve as an efficient adsorbent for the selective removal of trace ammonia from ammonia‐hydrogen fuel cell systems, significantly improving both the efficiency and longevity of the fuel cells. This work highlights the potential of P‐PDVB‐SO 3 H‐x as a promising candidate for enhancing ammonia‐hydrogen fuel cell performance, paving the way for further exploration of advanced adsorbent materials in energy applications.