Optimization for synthesis of high dispersion nanosized silver powder by orthogonal design

The Hydrazine hydrate (N₂H₄·H₂O) as the reducing agent, AgNO₃ as the source of Ag, the silver nanopowders with good dispersity were prepared by liquid phase reduction method. The morphology, composition and structure of the particles were investigated by transmission electron microscopy (TEM), X-ray fluorescence (XRF), and X-Ray diffraction (XRD), respectively. Single factor experiments were taken by studying the pH value and the selection of dispersers. Using the orthogonal design method, the optimal conditions to prepare the silver nanopowders were obtained by studying the effects of following factors, such as the concentration of AgNO₃, the doses of disperser and the temperature on the dispersion of the silver powder. The results show that under optimization conditions, the pure silver nanopowders with near-spherical shapes are synthesized using the AgNO₃(0.5mol·L^-1), N₂H₄·H₂O (0.5mol·L^-1), PVP as disperser, PVP/AgNO₃ mass ratio of 9:100, pH=8 at 30°C.