Synthesis of Mesoporous TiO-B Nanobelts with Highly Crystalized Walls toward Efficient H Evolution.

Mesoporous TiO is attracting increasing interest due to properties suiting a broad range of photocatalytic applications. Here we report the facile synthesis of mesoporous crystalline TiO-B nanobelts possessing a surface area as high as 80.9 m g and uniformly-sized pores of 6-8 nm. Firstly, P25 powders are dissolved in NaOH solution under hydrothermal conditions, forming sodium titanate (NaTiO) intermediate precursor phase. Then, HTiO is successfully obtained by ion exchange through acid washing from NaTiO via an alkaline hydrothermal treatment. After calcination at 450 °C, the HTiO is converted to a TiO-B phase. At 600 °C, another anatase phase coexists with TiO-B, which completely converts into anatase when annealed at 750 °C. Mesoporous TiO-B nanobelts obtained after annealing at 450 °C are uniform with up to a few micrometers in length, 50-120 nm in width, and 5-15 nm in thickness. The resulting mesoporous TiO-B nanobelts exhibit efficient H evolution capability, which is almost three times that of anatase TiO nanobelts.