Silver-Nanoparticle-Decorated Fused Carbon Sphere Composite as a Catalyst for Hydrogen Generation

Abstract

The dwindling supply of fossil fuels has resulted in a search for an efficient alternative energy source. Hydrogen gas offers an abundant, clean-burning supply of energy that can be readily produced over time via the water-splitting reaction of sodium borohydride (NaBH4). This study explored the synthesis of a novel catalyst comprised of silver nanoparticles supported on fused carbon spheres (AgNP-FCS). This composite catalyst was then tested for its ability to optimize the hydrolysis reaction of NaBH4. The fused carbon spheres (FCS) were synthesized via a sustainable source, namely a dextrose solution. The synthesized AgNP-FCS catalyst was characterized using transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The average diameter of silver nanoparticles on the catalyst was found to be 30 nm with 3.7% loading. This catalyst was tested under various reaction conditions, including temperatures, doses of NaBH4, and solution pHs. The activation energy of the reaction as catalyzed by AgNP-FCS was determined to be 37.0 kJ mol−1, which was competitive when compared to similar catalysts for this reaction. A study of the reusability of this catalyst suggests that the catalyst can be used multiple times consecutively with no loss in hydrogen generated. This material presents an opportunity for a sustainable catalyst to optimize the amount of hydrogen generated via the hydrolysis of NaBH4.