A facile route to aligned TiO2nanotube arrays on transparent conducting oxide substrates for dye-sensitized solar cellsElectronic Supplementary Information (ESI) available: Additional FESEM images and EDS result. See DOI: 10.1039/c0jm03689g/.

TiO2nanotube arrays (NTAs) on transparent conducting oxides (TCO) have attracted great attention due to the potential application in dye-sensitized solar cells (DSCs). Here, we introduce the template-assisted process for direct fabrication of aligned TiO2NTAs on TCO substrates, involving layer-by-layer adsorption and reaction (LBL-AR) assembled TiO2coating on ZnO nanorods (NR). Key factors of the fabrication process on the microstructures of TiO2NTAs are analyzed, and the geometry effects of TiO2NTAs on the performance and electron transport properties of DSCs are investigated by using electrochemical impedance spectra (EIS). An efficiency of 4.25% (under AM1.5 irradiation, 100 mW cm−2) is obtained from N719 sensitized 20 μm thick TiO2NTAs with a wall thickness of 20 nm, with Jsc= 8.2 mA cm−2, Voc= 0.81 V and FF = 63%. [ABSTRACT FROM AUTHOR]