The fast-paced economic climate of the world today has prompted a more thorough investigation into the field of alternative fuels. Increasing energy demands coupled with the crippling environmental and economic costs of carbon-based fuels, has aided in bringing this issue to a global level.¹ Hydrogen gas is among the most favorable of candidates being pursued in the search for a viable alternative to gasoline. Hydrogen is renewable in nature and produces no harmful emissions.² Current methods of hydrogen generation are limited in their efficiency due to the difficulties of harnessing and storing pressurized gas. Solid chemical storage in the form of metal hydrides, known for their hydrogen releasing capabilities, have been proposed as an alternative to these methods.³ Sodium borohydride (NaBH₄) is among the most favorable of metal hydrides for its high hydrogen content (10.8% wt) and superior energy density.^1-4 When coupled with water, sodium borohydride can generate up to 4 moles of dihydrogen gas per mole of NaBH₄ via a hydrolysis reaction. However, the oxidation of aqueous sodium borohydride is a slow process and the use of a catalyst is necessary for the reaction to procced at an appreciable rate. Transition metal catalysts, in particular Au, have been implemented in this reaction however, many suffer from oxidation degradation, therefore, the use of a support system is necessary.⁵ For this experiment, gold nanoparticles coupled with graphene and graphene oxide supports were used as the catalytic material for hydrogen evolution reactions. Overall, gold nanoparticles showed the highest reaction rate of 0.0018 mol-1 sec-1 at a standard concentration of NaBH₄, standard pH 7 and an increased temperature at 30°C.

References

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2. Haryanto, A.; Fernando, S.; Murali, N.; Adhikari, S. Current Status of Hydrogen Production Techniques by Steam Reforming of Ethanol: A Review. Energy Fuels 2005, 19, 2098–2106.
3. Dicks, A.L. Hydrogen generation from natural gas for the fuel cell systems of tomorrow. J. Power Sources 1996, 61, 113-124.
4. Huff, C.; Dushatinski, T.; Barzanjii, A.; Abdel-Fattah, N.; Barzanjii, K.; Abdel-Fattah, T.M. Pretreatment of gold nanoparticle multi-walled carbon nanotube composites for catalytic activity toward hydrogen generation reaction. ECS J Solid State Sci Technol 2017, 6, M69-M71.
5. Kochkar, H., Aouine, Ghorbel, A.,Berhault, G. Shape-Controlled Synthesis of Silver and Palladium Nanoparticles Using β-Cyclodextrin. Journal of Physical Chemistry 2011, 115, 11364-11373.