One-to-One Correspondence Growth Mechanism of Gourd-like SiOx Nanotubes

Abstract

In contrast with conventional thermal evaporation-based semiconducting oxide growth methods, gourd-like SiOx nanotubes (NTs) grown from Si substrates were achieved with incorporated Sn-embedded structures through the precontaminated SnO2 film surroundings. Interestingly, when Sn aggregations assembled as Sn nanoparticles were formed on the surface of the Si substrate, single gourd-like SiOx NTs were grown from the upper local region of the ternary alloy (Si–Sn–O) sphere, maintaining a one-to-one correspondent relationship between the ternary spheres and the Sn-embedded SiOx NTs. Both interfacial reaction-controlled and diffusion-controlled systems occurred stepwise at the smooth and rough surfaces, respectively. In addition, the elemental compositions and sizes of the final Sn-embedded SiOx NTs were influenced by the Sn concentration of the SnO2 film, the rate of In substitution by Sn in the supporting material In2O3, and the degree of carbothermal reduction of additional graphite powders.