Performance Of Metal Nanoparticles Research Articles

Controlled Synthesis of Palladium Nanoparticles with Size-Dependent Catalytic Activities Enabled by Organic Molecular Cages.

Particle size plays a key role in the performance of metal nanoparticles (MNPs). However, the size-controlled synthesis of MNPs still represents a challenging task. In this work, we revealed a strong solvent effect on the growth of palladium nanoparticles (PdNPs), which was directed by a porous [2 + 3] organic molecular cage (OMC, Phos-cage) containing triphenylphosphine moieties. PdNPs with different average diameters of 0.8, 1.2, and 3.3 nm supported by Phos-cage were obtained by simply varying the reaction media. The catalytic performance of such ultrafine PdNPs in the reduction of p-nitrophenol and a Suzuki-Miyaura coupling reaction has been studied, which clearly shows size-dependent catalytic activity and stability. The knowledge gained in this study, controlling the size of PdNPs supported by the OMC template in different solvents, will open new possibilities for size-controlled synthesis of ultrafine MNPs with high catalytic activity and stability.

Catalytic Performance of Metal Nanoparticles Supported by Ceramic Composite Produced by Partial Reduction of Solid Solution with Dopant

A composite with well-dispersed metal nanoparticles at a ceramic surface was produced by partial reduction of solid solution. It was found that a small amount of dopant, such as Al2O3, Cr2O3, or Sc2O3, accelerated the precipitation of the metal nanoparticles during the reduction. Catalytic performance of the composite for methanol reforming was evaluated. In the Ni-based catalysts, the dopant decreased the CO production by promoting a methanation reaction, while in the Co-based catalysts, the dopant did it by inducing a water–gas shift reaction. Co/MgO with Sc2O3 doping showed the most preferable reforming performance, high H2 production, and CO2 selectivity.