Formation of long-prismatic TiO2 nanocrystals upon the calcination of a mixture of titanium peroxo complex and sodium chloride

Abstract

The formation of long-prismatic titanium dioxide nanocrystals was detected upon carrying out a five-steps process consisting of the reaction of tetrabutoxytitanium with hydrogen peroxide, mixing the reaction product with sodium chloride, drying, calcination at 700 °C, and washing the material from salt. The crystals were formed in microcavities of the TiO₂ crystallite aggregate. The crosswise size of crystals was 40–90 nm, while their length reached 300–700 nm. According to the X-ray phase analysis, the polycrystalline sample consisted of two phases: anatase (92 wt.%) and rutile (8 wt.%). The long-prismatic crystals were formed only upon using NaCl in the synthesis. If this salt was not used, the resulting sample contained 32 wt.% anatase and 68 wt.% rutile.