“Surfactant-Free” Sodium Borohydride Nanoparticles with Enhanced Hydrogen Desorption Properties

NaBH4 is a promising material for hydrogen storage because of its high hydrogen density (10.8 mass %). However, the sluggish hydrogen kinetics and poor thermodynamics of the dehydrogenation process have hindered its practical applications. Core-shell structures that consist of isolated borohydride nanoparticle cores and metallic shells have been proposed as an alternative method to improve the hydrogen storage properties. In this context, we report on the synthesis of “surfactant-free” NaBH4 nanoparticle cores stabilized through the solvation of ionic salts. This alternative approach removes the need for surfactants for stabilizing nanosized NaBH4 and thus enables lower impurities during hydrogen release. In addition, the hydrogen release from these stabilized NaBH4 nanoparticles was found to start at an extremely low temperature of ∼50 °C because of the destabilization effect of the ions introduced.