Silica supported Pt/Ni alloys prepared via co-precipitation method

Pt/Ni alloyed nanoparticles have been prepared via co-precipitation method on crystalline silica support. The respective salt solutions were reduced using sodium borohydride (NaBH4) in an inert atmosphere at 353 K. Various Pt/Ni molar ratios were studied. H2-TPR studies revealed that total reduction of the metal ions occurred during the reduction stage while H2-TPD profiles show that there are four different types of the catalysts. Catalytic studies of these bimetallic catalysts demonstrate enhancements in the activity compared to Ni100. Catalyst with the best activity, Pt72Ni28, exhibits specific metal sites not seen in other catalysts. The existence of these metal sites is explained as due to the interaction between Pt and Ni nanoparticles. STEM analysis strongly indicates that the nature of the interaction is the formation of alloys between the metal particles while XPS demonstrates that Pt segregation occurs on the surface of the bimetallic particles.

Pt/Ni alloys supported on crystalline silica were prepared via co-precipitation technique using sodium borohydride as a reducing agent. The effect of Pt/Ni ratio on the hydrogenation of benzene was investigated. Pt72Ni28 exhibited superior catalytic activity compared to pure Ni and pure Pt catalysts. Results indicate that alloying and Pt segregation may have contributed to this enhanced activity.Figure optionsDownload as PowerPoint slide