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 Rh_0.48Fe_0.52/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 Rh_0.48Fe_0.52/g-C₃N₄ catalyst was calculated as 33.04 min^-1 and it showed an H₂ generation rate of $4214.02\hspace{0.17em}\text{mL\hspace{0.17em}}{\text{min}}^{-1}\hspace{0.17em}{\text{g}}_{\text{cat}}^{-1}$ at 298 K. Furthermore, the kinetic parameters (E _a ^#, ΔH ^#, ΔS ^#) of the hydrolysis of NaBH₄ catalyzed by the Rh_0.48Fe_0.52/g-C₃N₄ catalyst were elucidated. The findings demonstrated that the resulting Rh_0.48Fe_0.52/g-C₃N₄ catalyst was recyclable and retained 80.72% of the initial activity even after 10 runs.