Exploring the use of Impedance Spectroscopy for the study of current mismatch in Perovskite/Silicon Tandem solar cells

Perovskite/Silicon tandem solar cells have experienced a great interest in the last decade due to their high conversion efficiency which can exceed the Shockley–Queisser limit of a single junction solar cell. Although its promising role in the PV market, this technology has to overcome some issues. Among these, the current match of the two subcells constituting the tandem is a fundamental aspect. In this work a study of the current match of the two subcells is performed using impedance spectroscopy in the form of Nyquist plots. More in detail, two Perovskite/silicon solar cells are considered which differ only for the perovskite bandgap. The Nyquist plots analysis allows to understand if one of the subcell limits the tandem current and if the two subcells reaches the current maximum for the same current value, identifying the occurrence of a current match.