Remarkable Charge Separation and Photocatalytic Efficiency Enhancement through Interconnection of TiO 2 Nanoparticles by Hydrothermal Treatment

Although tremendous effort has been directed to synthesizing advanced TiO 2 , it remains difficult to obtain TiO 2 exhibiting a photocatalytic efficiency higher than that of P25, a benchmark photocatalyst. P25 is composed of anatase, rutile, and amorphous TiO 2 particles, and photoexcited electron transfer and subsequent charge separation at the anatase–rutile particle interfaces explain its high photocatalytic efficiency. Herein, we report on a facile and rational hydrothermal treatment of P25 to selectively convert the amorphous component into crystalline TiO 2 , which is deposited between the original anatase and rutile particles to increase the particle interfaces and thus enhance charge separation. This process produces a new TiO 2 exhibiting a considerably enhanced photocatalytic efficiency. This method of synthesizing this TiO 2 , inspired by a recently burgeoning zeolite design, promises to make TiO 2 applications more feasible and effective.