Fabrication Approach Impact on Solar-to-Hydrogen Evolution of Protonic Titanate-Derived Nano-TiO2

In terms of the traditional thermal transformation of TiO2 from protonic titanate, herein, we study the impact of the fabrication method of protonic titanate on photocatalytic hydrogen evolution of the derived TiO2 nanostructure. Present synthesis of TiO2 nanostructures involves the structure engineering of protonic titanate with four different synthesis strategies and a subsequent calcination process for conversion of TiO2 nanoflakes (hollow structure), nanorods, nanowires, and nanoflowers. Indeed, the TiO2 nanoflakes exhibit the highest H2 evolution rate of 3.63 mmol·g-1·h-1 among the four different TiO2 photocatalysts. With involvement of 3 wt % Pt, the corresponding H2 production rate of the TiO2 nanoflakes increases to 22.55 mmol·g-1·h-1, which is 3.18, 5.68, and 2.01 times higher than that of nanorods, nanowires, and nanoflowers, respectively. The band structure and photo/electrochemical analysis results propose that the negative conduction band position, fast photoinduced charge carrier separation, and abundant active sites contribute to excellent photocatalytic hydrogen evolution upon the TiO2 nanoflakes.