Jinjuan Xue

Effect of organic modifiers on the structure of nickel nanoparticles and catalytic activity in the hydrogenation of p-nitrophenol to p-aminophenol.

Spherical nickel nanoparticles with different sizes and different structures were prepared starting from nickel oxalate and using hydrazine hydrate as a reductant in the presence of citric acid, cetyltrimethylammonium bromide, Tween 40, and d-sorbitol as organic modifiers. The size and structure of the resultant nickel nanoparticles were affected by using different organic modifiers. All of the nickel nanoparticles showed higher catalytic activity and selectivity than the conventional raney Ni catalyst in the hydrogenation of p-nitrophenol to p-aminophenol. Although the catalytic activities of the resultant nickel nanoparticles generally increased with decreasing particle size, the structure of nickel nanoparticles also had an important impact on the catalytic activity.

Preparation of nickel nanoparticles with different sizes and structures and catalytic activity in the hydrogenation of p-nitrophenol

Spherical nickel nanoparticles with different sizes and different crystal structures were prepared by reducing nickel oxalate with hydrazine hydrate in the presence of PEG 200, PEG 6000, Tween 40, Tween 80, and sodium dodecyl sulfonate as organic modifiers. The organic modifiers with different functional groups play an important role in deciding the size and structure of the nickel nanoparticles. As compared to the conventional RANEY® Ni catalyst, all the as-prepared nickel nanoparticles showed high catalytic activity and selectivity in the hydrogenation of p-nitrophenol to p-aminophenol. The catalytic activities of the as-prepared nickel nanoparticles generally increased with decreasing the particle size. The crystal structure of nickel nanoparticles also had an important impact on the catalytic activity.