Graphene oxide/poly(3,4-ethylenedioxythiophene):polystyrenesulfonate layers on silver nanowire working electrodes enhance the power conversion efficiencies of dye-sensitized solar cells in a low temperature process

Abstract

In this study, silver nanowire (AgNW) networks were applied, for the first time, as transparent conductive layers for the working electrodes of dye-sensitized solar cells (DSSCs). To avoid corrosion of the AgNWs by iodine in the electrolyte, graphene oxide (GO) was used as a protective layer that isolated the AgNWs from the electrolyte; the effective prevention of corrosion probably arose from electrostatic repulsion between the electrolyte and the charged surface of the protective layer. After incorporation of 25% poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) into the GO, the power conversion efficiency (PCE) of the resulting GO/PEDOT:PSS–AgNW DSSC improved by 324%. The PEDOT:PSS doping led to the work function of the GO from 5.63 to 5.24 eV. The result may be because of decreasing the strength of the C–O dipole moment of the GO. The enhanced PCE can be attributed to the lower Schottky barrier between the AgNWs and the GO, due to the decreased work function of the GO.