Facile synthesis of core–shell-structured rutile TiO2 with enhanced photocatalytic properties

Abstract

Abstract Titanium oxide (TiO2) has received growing attention in photocatalyst is owing to its chemical stability and ecofriendly nature. Among the different phases of TiO2, pure anatase and mixed-phase TiO2 (Degussa P25) have been recognized as superior photocatalysts. Indeed, the mechanism of photocatalysis and the roles of various parameters in the process have been well documented for pure anatase TiO2 and Degussa P25. However, the pure rutile phase remains unexplored in the context of photocatalytic applications. Thus, herein, we report a one-pot method to modify the surface of pure rutile TiO2 and examine the factors that affect its photocatalytic performance. This modification was achieved by treating rutile TiO2 with H2O2 under microwave irradiation, which led to the formation of core-shell rutile TiO2 with a crystalline core and an amorphous shell bearing Ti3+ and Ti–OH species on the surface. The photocatalytic performance of this modified TiO2 species was enhanced threefold compared with that of unmodified rutile TiO2. This basic understanding of how to improve the photocatalytic performance of rutile phase TiO2 will play a crucial role in enhancing the catalytic performance of other metal oxides.