Thermally Stable Nanoporous Nanocrystalline TiO2 with a Bicrystalline (Anatase-Brookite) Framework Fabricated via Combining the Soft-Templating with Solid-Liquid Method

Abstract

Mesoporous anatase-brookite nanocrystalline titania was synthesized via a novel strategy relying on the combination of soft-templating and solid-liquid method (CSSL), in which the mesostructured titania hybrid was firstly synthesized via cooperative assembly between titanium sulphate and 1-hexadecyl-3-methylimidazolium bromide (C16mim+Br−), and subsequently ground with solid magnesium nitrate salt followed by heat-treatment in air. The resulting mesoporous titania material still possessed a large surface area of 150 m2/g even at 700°C of calcination temperature. The anatase phase in the titania framework transformed to brookite phase at 600°C. Moreover, the photocatalytic activities of as-synthesized titania materials in the degradation of methylene orange under ultraviolet irradiation were found to be determined by their surface areas and brookite phase contents.