Synthesis of monodispersed plate-shaped silver particles: with high tap-density and low radius-thickness ratio

Abstract

Purpose of this paper is to prepare monodispersed plate-shaped silver particles with high density and low radius-thickness ratio through wet-chemical reduction. This shape is suitable for preparing high silver content conductive paste with fine electrical conductivity. In this study, the reactant solutions were added by two parallel pipes to mix the two solutions evenly in the contact area. The sulfuric acid was used as a pH regulator, and polyvinylpyrrolidone (PVP K-30) was used as a capping agent, to control the morphology and particle size distribution of silver particles. The result shows that the combination of sulfuric acid and PVP play an important role on controlling the uniform crystal growth of silver particle. This probably because PVP are adsorbed on the surface of (111) plane to prevent the deposition of silver particles, and the PVP used as dispersant also slow the speed of reducing reaction. This make the flake silver particles grow slowly, and the plate-shaped silver particles with high tap-density and low radius-thickness ratio can be obtained. In addition, the resistivity of conductive silver paste that prepared with the as-synthesized plate-shaped flake silver particle was discussed in detail.

Keywords

• Plate-shaped silver particle
• Micron size
• Monodispersed
• High tap-density
• Low radius-thickness ratio