High Hydrogen Storage in Trigonal Prismatic Monomer‐Based Highly Porous Aromatic Frameworks

Abstract Hydrogen storage is crucial in the shift toward a carbon‐neutral society, where hydrogen serves as a pivotal renewable energy source. Utilizing porous materials can provide an efficient hydrogen storage solution, reducing tank pressures to manageable levels and circumventing the energy‐intensive and costly current technological infrastructure. Herein, two highly porous aromatic frameworks (PAFs), C‐PAF and Si‐PAF, prepared through a Yamamoto C─C coupling reaction between trigonal prismatic monomers, are reported. These PAFs exhibit large pore volumes and Brunauer–Emmett–Teller areas, 3.93 cm³ g⁻¹ and 4857 m² g⁻¹ for C‐PAF, and 3.80 cm³ g⁻¹ and 6099 m² g⁻¹ for Si‐PAF, respectively. Si‐PAF exhibits a record‐high gravimetric hydrogen delivery capacity of 17.01 wt% and a superior volumetric capacity of 46.5 g L⁻¹ under pressure‐temperature swing adsorption conditions (77 K, 100 bar → 160 K, 5 bar), outperforming benchmark hydrogen storage materials. By virtue of the robust C─C covalent bond, both PAFs show impressive structural stabilities in harsh environments and unprecedented long‐term durability. Computational modeling methods are employed to simulate and investigate the structural and adsorption properties of the PAFs. These results demonstrate that C‐PAF and Si‐PAF are promising materials for efficient hydrogen storage.