Performance improvement of perovskite heterojunction solar cell using graphene

The performance of a perovskite solar cell (PSC) is improved with a graphene electron transport layer (ETL) using Silvaco simulation software. Factors affecting solar cell performance such as absorber layer thickness, carrier mobility, doping concentration and carrier transport layer thickness have been studied. Higher carrier mobility, and fabrication cost are the most important factors toward the increment of the PSC utilization. Graphene is used here as an ETL due to its high carrier mobility, high optical transparency and good optical, mechanical and electrical properties at a low cost. The simulation is based on glass/ITO/Graphene/CH3NH3PbI3/Spiro-OMeTAD/Au structure which yields to photovoltaic (PV) parameters of Voc = 1.094 V, Jsc = 21.24 mA/cm2, FF = 90.185%, and power conversion efficiency of 20.95%. Moreover, the optimum thicknesses of 600 nm and 21 nm are determined for the perovskite absorber and ETL, respectively. •Graphene is employed as the ETL in PSC structure.•An optimum structure is obtained considering thickness and doping concentration variations.•The maximum PCE of 20.95% is achieved.