Research on preparation of spherical nanosized silvery powder

Using hydrazine hydrate as reducing agent, polyvinyl prorrolidone as protecting agent, the nanosized silver powder was synthesized by the chemical reduction method in a higher concentrated silvery nitrate solution. The preparation process of the nanosized silver powder was obtained through the study of the effects of the following factors such as the doses of reducing agent and protecting agent, the concentration of silver nitrate, temperature, the way to add reducing agent, pH value etc. on the particle size of the nanosized silvery powder and its morphology. The nanosized silver powder with the diameters of about 50 nm and homogeneous particle size distribution was prepared under the conditions of AgNO₃ concentration with 0.6 mol/L, PVP/AgNCh mole ratio with 1.5, hydrazine hydrate concentration with 0.6 mol/L, pH=5-6 and 60°C.