Synthesis of tellurium dioxide nanoparticles by spray pyrolysis

Tellurite glasses (amorphous TeO₂ based materials) have two useful optical properties, high refractive index and high optical nonlinearity, that make them attractive for a range of applications. Unlike other metal oxide nanoparticles that are prepared in large quantities by vapor phase processes, TeO₂ nanoparticles have not been prepared by such methods. Here, we describe the vapor-phase synthesis of TeO₂ nanoparticles from a dilute solution of telluric acid, Te(OH)₆, that is dispersed into fine droplets by an atomizer. These droplets are carried through a furnace, where they evaporate and where the precursors react to nucleate TeO₂ particles. The nanoparticles were characterized by TEM, XPS, FTIR and XRD. The effects of operating parameters on nanoparticle composition, production rate and size were also studied. This laboratory-scale process is capable of producing milligram to gram quantities of amorphous TeO₂ nanoparticles with primary particle diameters from 10 to 40 nm. copyright The Electrochemical Society.