Novel fabrication of solid-state NaBH4/Ru-based catalyst composites for hydrogen evolution using a high-energy ball-milling process

Abstract Solid-state NaBH 4 /Ru-based catalyst composites have been fabricated for hydrogen generation through a high-energy ball-milling process, providing uniform dispersion of resin-supported Ru 3+ catalysts among pulverized NaBH 4 (SBH) particles, so as to increase the contacts of SBH with active catalytic sites. Consequently, the gravimetric hydrogen storage capacity as high as 7.3 wt% could be achieved by utilizing water as a limiting reagent to overcome the issue of deactivated catalysts whose active sites are often blocked by precipitates caused by limited NaBO 2 solubility occurring in conventional aqueous SBH systems for hydrogen productions. Products of hydrolyzed SBH that greatly influence the gravimetric H 2 storage capacity are found to be most likely NaBO 2 ·2H 2 O and NaBO 2 ·4H 2 O from SBH/H 2 O reacting systems with initial weight ratios, SBH/H 2 O = 1/2 and 1/10, respectively, according to the TGA and XRD analyses.