Properties of silicon nanoparticles prepared by pulse discharge and ball milling

Abstract

In this paper, nano-silicon particles were prepared by pulse discharge and ball milling. Firstly, the bulk silicon material was gasified and melted at high temperature in the process of pulse discharge, and then the micro nanoparticles with small grain sizes, a high degree of disorder in crystal orientation and a certain amorphous structure were obtained by rapid condensation. The particles and internal grains were further refined by ball milling, and finally silicon nanoparticles with a high degree of amorphization, an average particle size of about 80.4 nm and a uniform size distribution were obtained. The results show that the longer the milling time, the smaller the grain size and the higher the proportion of the amorphous phase. The electrochemical performance analysis shows that the first charge specific capacity of Si pulse discharge is 3824 mA h g⁻¹, and the coulombic efficiency is 83.1%. After 100 cycles, the capacity retention rate is 14.2%, while the capacity retention rate of Si-15 h is 41.5%, which greatly improves the cycle life. The preparation method of silicon nanoparticles proposed in this paper is simple and effective, shortens the preparation time, and obtains silicon nanoparticles with a high degree of amorphization, which can provide a new method for the preparation of silicon nanoparticles.