Enhance hydrogen storage in lightweight solid-state systems based on Poly(vinylnaphthalene)

This article highlights the potential of poly(2-vinylnaphthalene) (PVN) as a novel light-weight solid-state hydrogen storage system for various applications. With an impressive theoretical gravimetric hydrogen capacity of 5.2 wt.-%, PVN stands out for its attractiveness as a hydrogen carrier. The material possesses advantageous characteristics, including moldability, low toxicity, and ease of storage, making it a promising candidate for both stationary and mobile hydrogen storage applications. Experimental findings demonstrate that PVN can be hydrogenated by up to 76 % utilizing an Ru/Al 2 O 3 catalyst at 250 °C for 24 h. Confirmation of the hydrogenation reaction, which results in poly(2-vinyldecalin), was achieved through characterization techniques such as FTIR, 1 H NMR, and spectroscopic ellipsometry. The study of the effects of hydrogen pressure and reaction time identified moderate conditions as favorable, though a further exploration of different catalysts is suggested for optimal conversion. A palladium-based catalyst was employed to release hydrogen from the hydrogenated polymer, demonstrating almost complete reversibility of the hydrogenation of poly(2-vinylnaphthalene) with a dehydrogenation yield of 90 %. • PVN shows potential as a lightweight solid-state hydrogen storage system, with theoretical hydrogen capacity of 5.2 wt.-% • PVN's low toxicity, moldability and easy storage make it a promising candidate for hydrogen storage applications. • Experimental results demonstrate hydrogenation of PVN, up to 76%, using an Ru/Al 2 O 3 catalyst at 250 °C for 24 h. • The dehydrogenation of hydrogenated PVN was conducted with a Pd/Al 2 O 3 catalyst at 250 °C (24 h) with a yield of 90%. • The reversibility of the controlled hydrogenation of poly (2-vinylnaphthalene) has been demonstrated.