Synthesis, characterization, and field-test of nanocatalysts for hydrogen production by hydrolysis of chemical hydrides

Abstract There is a growing concern related to increasing energy requirement and greenhouse gas emissions. Hydrogen gas is recognised as a desirable clean fuel and may be a sustainable solution. Hydrogen gas can be directly used as an anodic fuel for Proton Exchange Membrane Fuel Cell that converts chemical energy of hydrogen into electrical energy with no environmentally harmful by-products. Chemical hydrides with high hydrogen storage capacity in terms of gravimetric and volumetric efficiencies are the most promising candidates to supply pure hydrogen at room temperature. Among them, Sodium borohydride (SBH) and Ammonia borane (AB) have drawn a lot of interest as they are stable, non-flammable, nontoxic, and have a high hydrogen storage capability. Large amount of pure hydrogen gas is released during the hydrolysis of these chemical hydrides in presence of certain catalysts. The by-products are non-toxic, environmentally safe and can be recycled. Noble catalysts like Pt and Pd, used in the past to enhance the hydrogen production rate, do not seem to be viable for industrial application considering their cost and availability. Co and Ni borides are considered as good candidates for catalyzed hydrolysis owing to their good catalytic activity, low cost and effortlessly synthesis. Transition metals with varying (metal)/(Co + metal) molar ratio were doped in Co-B catalyst and the effect of metal doping on surface morphology, electronic interaction, and catalytic efficiency of the alloy catalyst powder on hydrogen production by hydrolysis of SBH and AB were studied. On the basis of characterization results, the role of each metal species, involved in hydrolysis and enhanced catalytic performance is discussed. The stability, reusability, and durability of these catalysts have also been investigated. Nanoparticle-assembled Co-B-P thin films on Ni foam (by electroless deposition), along with supported and unsupported Co-B nanoparticles over carbon films were synthesized by Pulsed Laser Deposition and studied for catalytic hydrolysis.