Enhanced growth of crystalline-amorphous core-shell silicon nanowires by catalytic thermal CVD using in situ generated tin catalyst

In this work, we prepared silicon nanowires (Si NWs) on both fluorine-doped SnO₂ (FTO) coated glass substrate and common glass substrate by catalytic thermal chemical vapor deposition (CVD) using indium film as the catalyst. It is confirmed that indium can catalyze the growth of Si NWs. More importantly, we found that tin generated in situ from the reduction of SnO₂ by indium can act as catalyst, which greatly enhances the growth of Si NWs on FTO substrate. The obtained Si NWs have a uniform crystalline-amorphous core-shell structure that is formed via vapor-liquid-solid and vapor-solid growth of silicon sequentially. This work provides a strategy to prepare Si NWs in high yield by catalytic thermal CVD using the low melting point metal catalysts.