Numerical investigation of the effect of interface conditions in HTM-free, printable WOx based and inverted perovskite solar cells
Résumé
One of the remaining issues, impeding the commercialization of the low cost and highefficiency perovskite solar cells (PSCs) is whether the halide perovskite materials have sufficient stability. Two considerable instabilities are the light-induced degradation and the scan-dependent performance, namely the hysteresis effect. Using experimental parameters and parameters obtained from atomistic modelling, the perovskite/Au, perovskite/TiOx, perovskite/WOx and perovskite/PCBM interfaces are numerically investigated and compared to the experimental current-voltage (J-V) and capacitance-voltage (C-V) characteristics.
Besides interface states, the effect of mobile ions is considered in the drift-diffusion approach for more realistic modelling. As a result, the experimental build in potential (Vbi) variation, open circuit voltage (VOC) loss, hysteresis effects and photocurrent degradation/recovery can be explained. The interplay between interface traps and mobile ions is assumed to lead the anomalous hysteresis, while local trap states are considered as the main cause of performance degradation as a function of time. Furthermore, a new approach is proposed for the
modelling of Kelvin Probe Force Microscopy (KPFM) of heterostructures in dark and under illumination. The KPFM measurement of silicon PN junctions is experimentally and theoretically investigated.