Abstract Sn-3.5%Ag (mass fraction, %) nanoparticles were synthesized by chemical co-reduction method and the morphology, phase composition and thermal behavior were studied. The effects of reducing agent concentration on nanoparticles size and the mechanism of nucleation and growth in the solution were studied. The results show that the concentration of reducing agent controls the rate of particle nucleation and growth in the solution, and the average particle size decreases with increasing the reducing agent concentration. The average radius of the nanoparticles reaches a minimum value of about 13nm when the reducing agent concentration is 0.25 mol/L. The nanoparticles consist of β-Sn and Ag3Sn phases. The minimum melting point is about 206 ℃. The increasing concentration of the reducing agent consumes a large amount of metal ions for instantaneous nucleation and inhibits further growth of the nanoparticles. Ag3Sn nucleates and grows in the solution preferentially. With the decrease of Ag atoms saturation in the solution, the composition of the nanoparticles is dominated by β-Sn. Finally forms nano-alloy consisting of Ag3Sn and β-Sn phases.
WANG Yao,MA Yunzhu,LIU Wensheng, et al. Effect of reducing agent concentration on the growth of Sn-Ag nanoparticles synthesized by chemical co-reduction method[J]. Materials Science and Engineering of Powder Metallurgy, 2018, 23(6): 607-613.
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2018, Vol. 23 
