Effects of compositional proportions, metal-ion concentration and pH conditions into the structural characteristics of Au, Pt and AuPt nanoparticles

Abstract

Nanometric metallic particles of Pt, Au and Au/Pt of different nominal compositions were synthesized using a chemical reduction method with a polymer (PVP) as the protecting agent. The effects of the gold ion concentrations and also of the concentration of the reducing agent compound, on the morphology and structural characteristics of the obtained gold nanoparticles have been explored. Particles with different pH reaction mixtures have been synthesized. High resolution transmission electron microscopy (HRTEM) observations have been used in the nanoparticles characterization. Depending of the pH reaction mixtures, different nanometric sizes and consequently different atomic structural configurations of the particles are obtained. Theoretical simulations based on molecular dynamics have been used to interpret some of the experimental results and also to get an insight on macroscopic properties such as: stability and catalytic activity.