Abstract
Perovskite solar cells exhibiting similar to 14-15% efficiency were experimentally measured using current-voltage (I-V) and capacitance-voltage (C-V) techniques in order to extract material and device properties, and understand the action of photovoltaic (PV) operation. Deep analyses were carried out on dark- and illuminated I-V curves, and dark C-V curves. Results were compared with those of graded bandgap solar cells fabricated on inorganic n-type window layers. These analyses according to a physicist's point of view lead to understand the perovskite solar cell as a graded bandgap solar cell built on a p-type window layer. I-V and C-V results show very similar behaviour and the principle of PV action is identical. Once the stability issues with perovskites are solved, these devices have very high potential of producing next generation solar cells reaching at least mid-20% efficiency values.