Photovoltaic devices with a PEDOT:PSS:WOx hole transport layer

Abstract

In this paper, we report a significantly improved fill factor (FF) of inverted poly(3-hexylthiophene) (P3HT) and indene-C₆₀ bisadduct (ICBA) organic photovoltaic devices via surface modification. The influence of the poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) (PEDOT:PSS) hole extraction layer (HEL) modified with tungsten oxide (WO_x) on inverted organic photovoltaics is studied. It is demonstrated that the PEDOT:PSS:WO_x modification leads to a remarkably high FF, while abruptly reducing the series resistance and at the same time increasing the shunt resistance. The efficiency increased from 3.93 to 5.37%, and it is demonstrated that PEDOT:PSS modified with WO_x HEL is an attractive material for high performance organic photovoltaic devices.