Enhancement of electrochemical performance of silicon nanowires by homostructured interface used as anode materials for lithium ion batteries

摘要

A novel and facile approach to fabricating long life silicon nanowires (SiNWs) via interface enhancement by structuring a silicon interface between SiNWs and metallic substrates from a nonequilibrium Si-Au composite based on conventional vapor-liquid-solid mechanism is successfully demonstrated in this paper. The building of a Si transition layer as an interface successfully converts the interface contact of the SiNWs on the substrates from point contact between the SiNWs and the stainless steel substrate into planar contact between the Si film and the stainless steel substrate. Although the interface modification process is very simple, the improved high stability of SiNWs from this way proves that it is a very promising strategy to get long life for high capacity anode materials used in lithium ion batteries. The building of a silicon homo-structural interface between assembled SiNWs and metallic substrates results in ultra long life for SiNWs. The retention capacity of the produced SiNWs is up to 2447 mA h g(-1) even after 100 cycles, delivering 80.92% of its second discharge capacity, presenting a very attractive cycling stability.