Cobalt impregnated magnetite-multiwalled carbon nanotube nanocomposite as magnetically separable efficient catalyst for hydrogen generation by NaBH4 hydrolysis

Abstract

Magnetite-multiwalled carbon nanotube nanocomposites were successfully synthesized and investigated as a catalyst for alkali free hydrolysis of sodium borohydride. Structure and morphologies of nanocomposites were studied by FT-IR, SEM-EDX, XRD and BET surface area analysis. SEM images of magnetite revealed the presence of roughly spherical nanoparticles of uniform shape and size. The introduction of carbon nanotubes caused the assembly of otherwise randomly arranged nanoparticles along the surface of carbon nanotubes. FT-IR analysis showed that the hydrophilic functional group introduced on the surface of carbon nanotubes during oxidation process are responsible for assembly of magnetite nanoparticles. The surface area of the nanocomposite was found to increase with an increase in the amount of carbon nanotubes. Catalytic activity of the nanocomposite materials was further enhanced by incorporating Co on their surface. The Co incorporated nanocomposite displayed high catalytic activity with H2 generation rate of 1213 mL min−1 g−1 at room temperature. Furthermore, catalyst could be easily recycled and displayed good stability for 5 recycles making it suitable for commercial application.