Novel fabrication of solid-state NaBH_4/Ru-based catalyst composites for hydrogen evolution using a high-energy ball-milling process

摘要

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 NaBCh 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_2O and NaBO_2-4H_2O from SBH/H_O reacting systems with initial weight ratios, SBH/H_2O= 1/2 and 1/10, respectively, according to the TGA and XRD analyses.