Nickel silicides prepared from organometallic polymer as efficient catalyst towards hydrogenation of phenylacetylene

Abstract A single-phase Ni 2 Si nanoparticle catalyst was prepared successfully by using temperature programmed pyrolysis method with polydimethylsilane-Ni(acac) 2 as precursor and was characterized by thermogravimetric analysis, X-ray diffraction, X-ray photoelectron emission microscopy, energy dispersive X-ray spectroscopy, and transmission electron microscopy. The pyrolysis temperature for generating pure Ni 2 Si in H 2 /Ar mixture is significantly lower than that for treatment in Ar. Ni 2 Si nanoparticles would be reduced to Ni nanoparticles by H 2 with increasing pyrolysis temperature (>600 °C). The catalytic hydrogenation of phenylacetylene on Ni 2 Si nanoparticles was investigated at 1.0 MPa hydrogen and 80 °C. The catalysts show suitable conversion of phenylacetylene and notable selectivity to styrene with 90%. In addition, catalytic performance on Ni 2 Si prominently improves after removing the SiO 2 layer around Ni 2 Si nanoparticles by alkali treatment.