H2 storage and capture are critical components in the development of clean and sustainable hydrogen energy. The current work investigates the H2 adsorption properties and storage on the Al-decorated porphyrin-like small porous C24N24 cluster using density functional theory calculations. Each Al site in the Al6C24N24 cluster can adsorb up to five H2 molecules, with an average adsorption energy of −0.30 eV. The impact of temperature and pressure on the hydrogen storage capacity of Al-decorated C24N24 clusters is also studied. A Kubas type mechanism and electrostatic interactions are found to be essential in the adsorption of H2 molecules on the Al-decorated C24N24. According to our findings, Al6C24N24 has a gravimetric density of 7.1 wt% H2. These findings demonstrate that the Al-decorated C24N24 may be a potential candidate for reversible H2 storage under normal conditions.
