Preparation and characterization of RhFe/g-C3N4 nanoparticles for efficient hydrolysis of sodium borohydride

Abstract

Highly effective graphitic carbon nitride-supported RhFe nanoparticles (RhFe/g-C3N4) were prepared using a simple wet impregnation-reduction method for the hydrolysis of sodium borohydride (NaBH4). The obtained Rh0.48Fe0.52/g-C3N4 catalyst was characterized using advanced analytical/spectroscopic techniques such as inductively coupled plasma-optical emission spectroscopy, scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, X-ray spectroscopy, and Fourier transform infrared spectroscopy. The catalytic activities of RhFe/g-C3N4 catalysts with varying Rh/Fe molar ratios were investigated, demonstrating superior catalytic activity compared to monometallic Rh and Fe. The initial turnover frequency value of the Rh0.48Fe0.52/g-C3N4 catalyst was calculated as 33.04 min-1 and it showed an H2 generation rate of 4214.02 mL min-1 gcat -1at 298 K. Furthermore, the kinetic parameters (Ea#, Delta H#, Delta S#) of the hydrolysis of NaBH4 catalyzed by the Rh0.48Fe0.52/g-C3N4 catalyst were elucidated. The findings demonstrated that the resulting Rh0.48Fe0.52/g-C3N4 catalyst was recyclable and retained 80.72% of the initial activity even after 10 runs. NaBH4 + 2H2O -> NaBO2(aq) + 4H2