(259e) Synthesis of Ru Nanoparticles Supported Over Carbon Film by Pulsed Laser Deposition for Hydrogen Production by Catalytic Hydrolysis of NaBH4

Sodium borohydride (NaBH₄), with H₂ storage capacity of 10.8 wt. %, produces pure hydrogen at room temperature in alkaline solution: this makes it a good source of hydrogen for fuel cell used for the portable and cellular technologies. However, catalysts play a vital role to control the hydrogen production during the hydrolysis reaction of NaBH₄. In the present work, Ru nanoparticles supported over carbon porous film (Ru-C) are synthesized using Pulsed Laser Deposition (PLD) and used as a catalyst in the hydrolysis of NaBH₄ to produce molecular hydrogen. Various Ar pressures (10 to 50 Pa) were used during deposition of carbon films to obtain extremely irregular and porous-carbon support with high surface area prior to Ru nanoparticles deposition which is done in-situ. The hydrogen generation rate produced by Ru-C catalyst film is significantly higher as compared to unsupported Ru film and commercial Ru-C powder. The catalyst films were characterized by SEM, TEM, XPS, EDS, XRD, Raman spectroscopy and BET surface area measurement to understand the enhanced activity of the catalyst. Morphological analysis showed that Ru nanoparticles with average size below 50 nm are well dispersed in the carbon matrix. Carbon films deposited under Ar atmosphere contain high amount of sp² coordinated graphitic carbon as observed by Raman spectra.  Nanoparticles produced by laser ablation process act as active catalytic centers for hydrolysis while the carbon support provides high initial surface area for the Ru nanoparticles with better dispersion and tolerance against aggregation. The catalytic activity of the film was found to be dependent on the amount of Ru loading. Kinetic studies on the hydrolysis reaction of NaBH₄ with Ru-C catalyst film reveal that the concentrations of both NaBH₄ and NaOH have essentially no effects on hydrogen generation rate.