title: Novel ZnO nanostructured electrodes for higher power conversion efficiencies in polymeric solar cells.
abstract: 1-Dimensional nanostructured ZnO electrodes have been demonstrated to be potentially interesting for their application in solar cells. Herein, we present a novel procedure to control the ZnO nanowire optoelectronic properties by means of surface modification. The nanowire surface is functionalized with ZnO nanoparticles in order to provide an improved contact to the photoactive P3HT:PCBM film that enhances the overall power conversion efficiency of the resulting solar cell. Charge extraction and transient photovoltage measurements have been used to successfully demonstrate that the surface modified nanostructured electrode contributes in enhancing the exciton dissociating ratio and in enlarging the charge lifetime as a consequence of a reduced charge recombination. Under AM1.5G illumination, all these factors contribute to a considerably large increase in photocurrent yielding unusually high conversion efficiencies over 4% and external quantum efficiencies of 87% at 550 nm for commercially available P3HT:PCBM based solar cells. The same approach might be equally used for polymeric materials under development to overcome the record reported efficiencies.
authors: Department of Microsystems, IKERLAN S. COOP, Goiru Kalea, 2, 20500 Arrasate-Mondragon, Spain E-20500.
authors: Jon
authors: J
authors: Ajuria
authors: Ikerne
authors: I
authors: Etxebarria
authors: Eneko
authors: E
authors: Azaceta
authors: Ramón
authors: R
authors: Tena-Zaera
authors: Nuria
authors: N
authors: Fernández-Montcada
authors: Emilio
authors: E
authors: Palomares
authors: Roberto
authors: R
authors: Pacios