Preparation of porous PVDF-NiB capsules as catalytic adsorbents for hydrogen generation from sodium borohydride

Porous poly(vinylidene fluoride) (PVDF)-NiB capsules were prepared by phase inversion of PVDF, nickel salt and sodium borohydride (NaBH₄) mixtures in water. During the process, nickel salt was reduced to NiB particles by NaBH₄, and the excess NaBH₄ was hydrolyzed to produce hydrogen gas bubbles which aided the formation of the large holes inside the porous capsules. It was proved that the porous capsules can adsorb about 33 wt.% NaBH₄ in THF/NaBH₄ solution for about 4 h. Most of NiB particles were attached on the surface of the porous capsules with inside holes according to the observation of scanning electron microscopy (SEM) and EDS. The special structure of the capsules was successfully used as catalysts and container simultaneously for hydrogen production via catalytic hydrolysis of NaBH₄ in aqueous solution.