Graphene oxide-molybdenum oxide composite with improved hole transport in bulk heterojunction solar cells

Solution processed hole transport layer based on graphene oxide (GO) and molybdenum oxide (MoO3) composite in bulk heterojunction organic solar cell (OSC) devices offer low cost, improved performance compared to conventional organic solar cells. Here, we have made a study comparing the power conversion efficiency (PCE) of this composite to the pristine GO and MoO3 as a hole transport layer in the organic photovoltaics. The devices with the composite shows optimized performance with PCE of similar to 5.1%, while the pristine GO and MoO3 display 1.59% and 2.5%, respectively. These differences are attributed to the lower short circuit current (J(sc)) and thereby lower fill factor (FF) with respect to the GO and MoO3. Nevertheless, the composite based devices exhibits improved optical absorption and photoluminescence quenching as compared to pristine interface layer. This study intends to highlight efficient modulation of the interface barrier of hole transport layer which allow us to give faster transport and extraction of the charge carrier efficiently at the electrodes.