Synthesis, Characterization, and Growth Mechanism of Tellurium Nanotubes

A simple hydrothermal reduction method, employing sodium tellurate (Na 2 TeO 4 ·2H 2 O) as tellurium source and formamide (HCONH 2 ) as a reductant, was used to prepare and investigate tellurium nanotubes. The diameters of the nanotubes range from 200 to 600 nm and their lengths from 4 to 15 μm. Unlike studies reported previously, 1,2 a series of electron microscopy characterization results suggests that the growth of tellurium nanotubes under the present experimental conditions is governed by a nucleation−dissolution−recrystallization growth mechanism: sphere-like tellurium nanoparticles initially formed in the hydrothermal system; the sphere-like nanoparticles were gradually dissolved to generate free tellurium atoms in the solution; these tellurium atoms were renewedly transferred onto the surfaces of the sphere-like nanoparticles and evolved into groove-like nanorods; the groove-like nanorods could be grown into tellurium nanotubes eventually.