Highly ordered 1D TiO2 nanotube arrays are fabricated and applied as nanocontainers and electron transporting material in CH3NH3PbI3 perovskite solar cells. The optimized device shows a power conversion efficiency of 14.8%, and improved stability under an illumination of 100 mW cm-2. This is the best result based on 1D TiO2 nanostructures so far. © 2015 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim.