A light-weight sponge catalyst for hydrogen generation from liquid hydrogen carriers

In this work, we report a sponge catalyst for hydrogen generation from liquid hydrogen carriers. Commercial melamine formaldehyde (MF) sponge is grafted with polyvinyl alcohol by acid catalyzed acetalization with formaldehyde. The obtained polyvinyl formal/MF (PVF/MF) composite sponge combines the intrinsic light-weight, high porosity and fast liquid absorbing rate of the MF sponge with enhanced metal binding strength. By a simple impregnation-sodium borohydride reduction method in aqueous solution, metals can be uniformly loaded to the fibers of the PVF/MF sponge with strong adhesion. The metal loaded PVF/MF sponge has unique advantages as a catalyst for hydrogen generation from liquid hydrogen carriers, including high activity, high hydrogen storage density, easy catalyst recycling and quasi solid state during H2 generation, as demonstrated in the applications of NaBH4 solution and thermal dehydrogenation of perhydro N-ethylcarbazole.