Development of effective catalysts for hydrogen generation from sodium borohydride: Ru, Pt, Pd nanoparticles supported on Co3O4

Abstract

In this study, Ru, Pt, Pd-based catalysts supported on Co3O4 with microwave irradiation-polyol method is used for the hydrogen generation from NaBH4 hydrolysis. Surface morphology and structural properties of the catalysts were studied by using X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and inductivity coupled plasma-mass spectrometer (ICP/MS). In addition to, an on-demand hydrogen generation system, which can produce hydrogen from NaBH4 solution and in order to determine the activity of the prepared catalysts, is designed by our group. The effects of solution temperature, amount of catalyst and the initial concentrations of NaBH4/NaOH on the hydrogen generation rate are investigated. The highest hydrogen generation rate at 25 οC is obtained from Ru–Co3O4 catalyst with 6514 ml/gcat.min. In addition, the highest hydrogen generation rate from hydrolysis of NaBH4 with Pt–Co3O4 catalyst is achieved at 55 οC as 23916 ml/gcat.min. The Ea values were calculated as 28.26 kj mol−1, 43.52 kj mol−1 and 65.82 kj mol−1 for Ru–Co3O4, Pt–Co3O4 and Pd–Co3O4, respectively. Furthermore, it is observed that the increase in solution temperature had a very positive effect on the hydrogen generation rate of Pd based catalyst.