Study of the reverse saturation current and series resistance of p-p-n perovskite solar cells using the single and double-diode models

The effects of the offset level and of the doping level in the perovskite layer upon both the reverse saturation current (J0) and the series resistance (Rs) of p-p-n perovskite solar cells have been researched in this paper, using five different materials such as spiro-OMeTAD, Cu2O, CuSCN, NiO and CuI, as Hole Transporting Material (HTM). The analysis was carried out by means of the single and double-diode models of a solar cell and of genetic algorithms based on optimization technique, in order to extract the desired parameters. The minor degradation of J0 and Rs has been found for the condition offset equal to zero and for the highest doping level in p-type perovskite layer. Also, a comparison has been made of the behavior of two reverse saturation currents (J01 and J02). The power conversion efficiency (PCE) has shown to be more strongly dependent on J02 than on J01. Results obtained in this work can be used to improve the manufacturing process of these devices.