Photocatalytic water splitting on Au/HTiNbO5 nanosheets

The layered potassium titanium niobate, KTiNbO5, is known as a photocatalyst for hydrogen production from water splitting under UV light. Here we show that titanium niobate nanosheets with a slit like framework can be obtained by exfoliation of KTiNbO5 followed by proton exchange. Gold nanoparticles were deposited on the titanium niobate nanosheets using deposition-precipitation (DP), photo-deposition (PD) and impregnation (IMP) method in order to improve photocatalytic hydrogen production from water splitting. These catalysts were characterized by powder X-ray diffraction patterns (XRD), inductively coupled plasma mass spectrometry (ICP-MS), UV-visible spectroscopy (UV-vis), and Transmission Electron Microscopy (TEM). The gold loaded titanium niobate nanosheets prepared by the DP method consisted of a good metal-semiconductor interface which allowed for a much higher efficient electron-hole separation. In this paper, we developed a facile method of preparing titanium niobate nanosheets containing gold nanoparticles. The titanium niobate nanosheets with Au cocatalyst prepared by the DP method showed a uniform dispersion of gold nanoparticles with an average gold particle size of 3 nm and exhibited an ultra-high photocatalytic water splitting activity, which was 56 times higher than that exhibited by the origin KTiNb05 photocatalyst. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.