Highly active heteropolyanions supported Co catalysts for fast hydrogen generation in NaBH4 hydrolysis

Cobalt borate catalysts for hydrogen production via hydrolysis of sodium borohydride

“…Catalysts containing noble metals (Pt, Rh, Ru) have shown the best performance in this process [10][11][12], but their high cost makes them prohibitive for wider applications. Cobalt-based catalysts have recently emerged to potentially replace noble metals in NaBH 4 hydrolysis [13], including Co nanoparticles [14][15][16], metallic cobalt [7,17], cobalt salts [7,8,17,18], cobalt oxides [16,[18][19][20], Co-B hollow spheres [21], and supported Cocontaining catalysts [22][23][24][25][26]. However, most of the work in this area has been devoted to cobalt boride, Co x B, either in its pure form [27][28][29][30][31] or with dopants (Ni, Fe, Cu, W, Cr, Mo, Mn, and P) [25,[32][33][34][35].…”

Heterogeneous and homogenous catalysts for hydrogen generation by hydrolysis of aqueous sodium borohydride (NaBH4) solutions

“…Bennici et al. . have reported a better performing polyanion complex (in terms of hydrogen generation rate) as a support for cobalt nanoparticles, but the large weight of the support per g of cobalt metal would probably render such systems unsuitable for portable applications which are becoming increasingly popular at present.…”

“…This system was improved further by Rakap et al [109], who synthesized a hydroxyapatitesupported cobalt nanoparticle catalyst providing 25,600 turnovers in the hydrolysis of basic sodium borohydride. Bennici et al [110]. have reported a better performing polyanion complex (in terms of hydrogen generation rate) as a support for cobalt nanoparticles, but the large weight of the support per g of cobalt metal would probably render such systems unsuitable for portable applications which are becoming increasingly popular at present.…”

Hydrogen generation from LiBH 4 solution catalyzed by multiwalled carbon nanotubes supported Co–B nanocatalysts for a portable micro proton exchange membrane fuel cell application

“…However, thermodynamic and kinetic limitations caused by strong covalent and ionic bonds greatly restrain the practical application of LiBH 4 as a reversible hydrogen storage material. Hydrolysis of LiBH 4 is of interest for hydrogen generation, because its hydrogen generation capacity is 8.6 wt% [6], which is higher than 5.8 wt% for NH 3 BH 3 [7] and 7.2 wt% for NaBH 4 [16] (taking anhydrates into account).…”

“…However, agglomeration of CoeB catalysts and sticking of fine powders during exothermic reaction restrict the hydrogen generation kinetics due to the reduction of surface area. In order to overcome agglomeration, the effective method is supporting particles into/onto porous matrix [16,17] or incorporating CoeB with other transition elements such as chromium, phosphorus or nickel [18e22]. The widely used supporting materials are metal oxides, nickel foam, activated carbon and clay minerals [16e31].…”