Enhanced Performance of Polymer Solar Cells with PSSA-g-PANI/Graphene Oxide as Hole Transport Layer

Abstract

Hole transport layer (HTL) has always been used for high performance polymer solar cells (PSCs) because of efficient hole extraction from active layer to anode and lowering the contact resistance between active layer and anode. Although PEDOT:PSS has commonly been used as a HTL, it has detrimental problems with low electrical conductivity, acidic nature and large aggregates. As an alternative to PEDOT:PSS, we previously synthesized poly(styrenesulfonic acid)-graft-polyaniline (PSSA-g-PANI) which is a self-doped conducting copolymer, and reported significant enhancement of the power conversion efficiency (PCE) of PSCs when it was used as a HTL of PSCs. In this work, we prepared PSSA-g-PANI/graphene oxide (GO) composite by adding GO into PSSA-g-PANI and used the composite as HTL of PSCs for the purpose to further improve the PCE. When the PSSA-g-PANI/GO (95/5) composite was used as HTL, the PCE of PSCs was improved by about 10% as compared to that without GO.