Controllable synthesis of Si@SiC plate@Si3N4 whisker with core-shell structure and their electrochemical performances

The Si@SiC@Si 3 N 4 composites with core-shell structure were synthesized by a catalytic nitridation method, Si powder and phenolic resin were used as the raw materials, ferric nitrate was used as the catalyst. The effect of catalyst content on synthetic powders was investigated. The results indicated that when no catalyst was added, a small amount of whiskers were formed on the surface of the Si powder. The addition of the catalyst could effectively promote the formation of SiC and Si 3 N 4 , and a double-layer core-shell structure was formed in which the inner shell is a SiC plate and the outer shell is a Si 3 N 4 whisker. However, excessive addition of the catalyst caused the resulting Si 3 N 4 whiskers to distorted and intertwined. The prepared composite materials (5 wt% catalyst) exhibited good rate capability and a specific capacitance of approximately 200 F/g at 0.5–3 A/g. Finally, the possible formation mechanism of this core-shell structure was proposed.