High-capacity hydrogen adsorption in topologically semimetallic Macroporous carbon allotrope

Hydrogen, as a recyclable and eco-friendly energy carrier, offers a viable alternative to fossil fuels, necessitating the development of efficient storage solutions. Here, we have proposed a Macroporous two-dimensional carbon allotrope (MTDCA), TPO-graphene, as a promising hydrogen storage material. MTDCA exhibits exceptional potential for high-capacity storage, owing to their lightweight structure and extensive surface area. The band structure and Berry phase analysis reveal eight Dirac points near the Fermi level, which give rise to multiple non-trivial topological edge states, significantly improving TPO-graphene’s electrical conductivity. In addition, the intense interaction between alkali metal atoms and TPO-graphene enhances hydrogen adsorption, positioning it as an excellent candidate for hydrogen storage. Specifically, Li, Na, and K exhibit hydrogen storage capacities of 6.5 wt%, 7.0 wt%, and 7.5 wt%, respectively. Moreover, TPO-graphene’s exceptional structural stability and high mechanical strength further enhance its versatility in various applications.