PSSA–g–PANI/Graphene Oxide Composite as a New Class of Hole Transport Layer for Enhanced Performance of Polymer Solar Cells

Abstract

A new class of hole transport layer (HTL), which is composed of poly(styrene sulfonic acid) grafted with polyaniline (PSSA–g–PANI) and graphene oxide (GO), was prepared by adding GO into PSSA–g–PANI aqueous solution. The PSSA–g–PANI/GO composites exhibit high optical transparency and high electrical conductivity. When the composite with 2.5 wt% GO loading was used as HTL material for the device based on poly(3-hexylthiophene) and PC61BM, the device exhibits an enhanced power conversion efficiency (PCE) of 4.23%, which is 23% higher than the PCE of device with the conventional HTL material, PEDOT:PSS. This enhancement of PCE arises mainly from an increase of the short-circuit current density due to higher optical transparency and higher electrical conductivity of PSSA–g–PANI/GO composite.