Hydrothermal synthesis of 1D TiO2 nanostructures for dye sensitized solar cells

Mono-dimensional titanium oxide nanostructures (multi-walled nanotubes and nanorods) were synthesized by the hydrothermal method and applied to the construction of dye sensitized solar cells (DSCs). First, nanotubes (TiNTs) and nanotubes loaded with titanium oxide nanoparticles (TiNT/NPs) were synthesized with specific surface areas of 253 m(2)/g and 304 m(2)/g, respectively. After that, thermal treatment of the nanotubes at 500 degrees C resulted in their transformation into the corresponding anatase nanorods (TiNT-Delta and TiNT/NPs-Delta samples). X-ray diffraction and Raman spectroscopy data indicated that titanium oxide in the pristine TINT and TINT/NP samples was converted into anatase phase TiO2 during the heating. Additionally, specific surface areas and water adsorption capacities decreased after the heat treatment due to the sample agglomeration and the collapse of the inner nanotube channels. DSCs were fabricated with the nanotube TiNT and TINT/NP samples and with the anatase nanorod TiNT-Delta and TiNT/NPs-Delta samples as well. The highest power conversion efficiency of eta = 3.12% was obtained for the TINT sample, despite its lower specific surface compared with the corresponding nanoparticle-loaded sample (TINT/NP). (C) 2011 Elsevier B.V. All rights reserved.