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

초록

In contrast with conventional thermal evaporation-based semiconducting oxide growth methods, gourd-like SiO_x 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 SiO_x 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 SiO_x 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 SiO_x 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. © 2016 American Chemical Society.