High performance organic photovoltaics with zinc oxide and graphene oxide buffer layers

Abstract

We report air stable inverted organic photovoltaics (OPVs) incorporating graphene oxide (GO) and solution processed zinc oxide (ZnO) as hole transport and electron transport layers, respectively. Both the hole transport layer and the electron transport layer (HTL and ETL) are of advantage in high transparency and environmental stability. The use of GO and ZnO in poly(2,7-carbazole) derivative (PCDTBT):fullerene derivative (PC₇₀BM)-based inverted OPVs leads to an improved device stability and enhanced high open circuit voltage (V_oc) of 0.81 V, a short-circuit current density (J_sc) of 14.10 mA cm⁻², and a fill factor (FF) of 54.44 along with a power conversion efficiency of 6.20%.