title: One-Dimensional Self-Standing TiO2Nanotube Array Layers Designed for Perovskite Solar Cell Applications.
abstract: Nanotube (NT) layers of TiO2are important one-dimensional nanostructures for advanced applications. ZnO nanowire arrays prepared through electrochemical deposition with tuned morphological properties are converted into anatase TiO2NTs by using a titanate solution adjusted to an ad hoc pH. The tubes are polycrystalline and their diameter and length can be tuned to obtain nanostructures of tailored dimensions. The layers are integrated in CH3NH3PbI3perovskite solar cells (PSCs). Their morphology is optimized for maximum performance and is compared to mesoscopic TiO2PSCs. As compared to the latter, the use of NTs improved the perovskite absorbance in the green-to-near-infrared solar spectral region. Moreover, it is shown that the surface treatment of the TiO2NTs with TiCl4optimizes the interface between the oxide and CH3NH3PbI3, which leads to better charge injection between the perovskite layer and the TiO2NTs. The current density-voltage curve hysteresis index is low for the best NT morphology and significantly increases with tube length and diameter.
authors.affiliation: PSL Research University, Chimie ParisTech-CNRS, Institut de Recherche de Chimie Paris, UMR8247, 11 rue P. et M. Curie, 75005 Paris (France).
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: PSL Research University, Chimie ParisTech-CNRS, Institut de Recherche de Chimie Paris, UMR8247, 11 rue P. et M. Curie, 75005 Paris (France).
authors.forename: Thierry
authors.initials: T
authors.lastname: Pauporté
keywords: TiO2 nanotubes; electrochemical deposition; hybrid perovskites; hysteresis index; solar cells