The Effect of Graphene as an Electrode Material on Power Conversion Efficiency of Polymer Solar Cells

The production of energy using solar cells could reduce our dependence on fossil fuels and greenhouse gas emissions. Polymer solar cells in comparison with the other types, with having lower power conversion efficiency, have advantages such as low weight, high flexibility, high absorption coefficient and lower fabrication cost related to silicon solar cells. These devices are made from three main components: photoande, the active layer and a cathode. Photoande is the first component in contact with the sunlight. This layer must be transparent and have high electrical conductivity and low resistance. The work function of photoande must be high to collect the holes produced by the active layer. The cathode should have high conductivity and low work function to collect electrons. This review paper introduces the graphene, its physical properties, its application as electrodes and its effect on power conversion efficiency of polymer solar cells.