Ultrasound-assisted synthesis of monodisperse Ru–B amorphous alloys with enhanced catalytic activity in maltose hydrogenation

Abstract

Monodisperse Ru–B amorphous alloy catalysts were synthesized by ultrasound-assisted chemical reduction of (NH4)2RuCl6 with BH 4 − . With the characterization of X-ray diffraction (XRD), selective area electronic diffraction (SAED), X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM), the resulting Ru–B nanoparticles were identified to be amorphous alloys ranging in size from 2.4 to 4.9 nm. During liquid-phase maltose hydrogenation, the as-synthesized Ru–B catalyst was extremely active compared to the regular Ru–B obtained via the reduction of RuCl3 with BH 4 − . The Ru–B sample prepared under ultrasonication with 60 W was proven to be the most active catalyst. Its catalytic activity was nearly 11 times that of industrial Raney Ni, and could be used repetitively for more than six times without significant deactivation.