Reductive Preparation of Blue TiO2 via Deposition of Aluminum

Abstract

Improving catalysis efficiency and reducing production cost attract extensive interest for the study of photocatalyst. Herein a blue titania crystal with aluminum atoms modified on the surface was prepared by aluminum reduction and deposition. The blue titania displays a unique core-shell structure with crystallization nuclei inside and with oxygen vacancies and aluminum atoms outside. And the blue titania shows excellent photocatalytic and electroch¬emical performance under simulated sunlight. Under high vacuum, with vapored aluminum atoms being deposited on titania nanocrystals, Ti4+ is reduced to Ti3+, which creates a large number of oxygen vacancies on the surface. Additio¬nally, moderate amounts of aluminum atoms coated on titania become photo-induced charge carrier traps, facilitating the separation and transport of charge carriers, which enhances the photocatalytic capability. TiO2-Al0.36 exhibits the best photocatalytic performance, degrading methyl orange in 8 min, and it shows excellent photochemical property with the photocurrent of 1.47 mA•cm-2, which is more than 8 times as high as that of pristine titania (0.17 mA•cm-2).