Melting Of Zinc And Silver Nanoparticles

Melting of metallic nanoparticles changes with the change in particle size, which is an important parameter to material selection and process design. So it is necessary to study the melting behavior of metallic nanoparticles. But experimental studies on the size-dependent melting of metals are regretfully limited to the sample preparation methods and inhibited further investigations on this subject.In this subject, our research group has conducted extensive studies on the melting of metallic nanoparticles, breaking the previous system. The melting of Fe nanoparticles and Cu nanoparticles embedded in SiO2 prepared by using mechanical milling was investigated. And the melting of Sn nanoparticles embedded in LiF was studied.Based on the above research, Zn nanoparticles embedded in different matrix are prepared by using mechanical milling in this paper. The melting behavior was explored.(1) With Al2O3 and LiF as the matrix, the particle size distribution of Zn nanoparticles prepared by using mechanical milling was narrow.(2) Preparation of Zn nanoparticles embedded in Al2O3 by mechanochemical synthesis, the size of Zn nanoparticles decreased to 23 nm and the melting point depression is 17℃ in comparison with bulk Zn. By direct milling of Zn and LiF powders, the size of Zn nanopartucles decreased to 16 nm and the melting point depression is 22℃ with bulk Zn. The melting point depression of Zn nanoparticles is in accordance with theoretical calculations.In addition, Ag nanoparticles embedded in different matrix are prepared by using mechanical milling in this paper. Preparation of Ag nanoparticles embedded in C by mechanochemical synthesis, the size of Ag nanoparticles decreased to 19 nm and the melting point depression is 17℃ in comparison with bulk Ag. The melting point depression of Ag nanoparticles is in accordance with theoretical calculations. The melting of Ag nanoparticles is explored and riched the experimental data.