Transformation of microporous titanium glycolate nanorods into mesoporous anatase titania nanorods by hot water treatment

High surface area titanium glycolate microporous multi-faceted nanorods were synthesized from the reaction of titanium alkoxides (Ti(OEt)4, Ti(OiPr)4, or Ti(OnBu)4) with ethylene glycol, using a sol–gel reflux method. The specific surface area of the as-synthesized titanium glycolate nanorods obtained from Ti(OEt)4 is ~480 m2/g. A hot water treatment at 90 °C for 1 h transformed the titanium glycolate microporous nanorods into mesoporous anatase TiO2 nanorods. The shape of the nanorods was conserved after hot water treatment and the microporous to mesoporous transformation took place without significant change in the surface area (477 m2/g). Micro Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, solid state NMR, and nitrogen adsorption/desorption were used to characterize the samples. As a demonstration of potential applications, the thus formed mesoporous anatase TiO2 nanorods were tested for their photocatalytic efficiency in the degradation of crystal violet, and a photodegradation mechanism is proposed.