Efficient synthesis of titania nanotubes and enhanced photoresponse of Pt decorated TiO₂ for water splitting

Abstract

We investigated the effect of HMT (hexamethylenetetraamine) on the anodic growth of TiO₂ nanotube arrays. The tube length increases to 4.3 μm with HMT concentration increasing to 0.04 mol·L^-1. Adsorption of HMT on the TiO₂ surface is shown to markedly decrease the chemical dissolution rate of tube mouth, resulting in longer nanotube length. Furthermore, Pt nanoparticles were successfully deposited on the surface of TiO₂ nanotubes by ac electrodeposition method. The TiO₂/Pt composites were characterized by field emission scanning electron microscope (FESEM), X-ray photoelectron spectra (XPS), and photoelectrochemistry. An enhancement in photocurrent density has been achieved upon modification of TiO₂ nanotubes with Pt nanoparticles.

Key words： TiO₂ nanotube arrays; HMT; TiO₂/Pt; Photocurrent density

Acknowledgements

Funding for this work is from the National Natural Science Foundation of China (Grant No. 20776103) and the China Postdoctoral Science Foundation (No. 20080440678).

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