\({\text{Ta}}_{\text{2}}{\text{O}}_{\text{5}}\)Nanowires, Nanotubes, and\({\text{Ta}}_{\text{2}}{\text{O}}_{\text{5}}\text{/}{\text{SiO}}_{\text{2}}\)Core-Shelled Structures: From Growth to Material Characterization

Abstract

One-dimensional polycrystalline ${\text{Ta}}_{\text{2}}{\text{O}}_{\text{5}}$nanostructures are synthesized by the annealing of the ${\text{SiO}}_{\text{2}}$nanowires at 950°C in a reductive Ta vapor ambiance. The formation mechanism of ${\text{Ta}}_{\text{2}}{\text{O}}_{\text{5}}$nanostructures is discussed and illustrated in detail. The nucleation and grain growth of ${\text{Ta}}_{\text{2}}{\text{O}}_{\text{5}}$crystals were investigated during the formation of the ${\text{SiO}}_{\text{2}}$/ ${\text{Ta}}_{\text{2}}{\text{O}}_{\text{5}}$core-shelled structures. The diffusion-controlled growth is suggested to be the rate-determining step for the diffusion of the Ta atoms through the ash layer to react with O atoms and substitute Si atoms.