Modeling the Impact of Contact Resistance and Interfacial Losses in NiOx Based Perovskite Solar Cells Using MATLAB

Abstract

Interfacial charge recombination and ohmic contact resistance at the hole transport layer heterojunction represent fundamental barriers limiting the performance of inverted perovskite solar cells. This work presents a quantitative numerical investigation of contact degradation at the nickel oxide/perovskite interface using an implicit single-diode equivalent circuit model implemented in MATLAB. Through a parametric sweep of series resistance from  to 5.0,  we systematically isolate ohmic losses from the device's intrinsic performance. The simulation results demonstrate that while open-circuit voltage and short-circuit current density show minimal sensitivity to resistive transport barriers, the fill factor undergoes a significant non-linear reduction from 74.1% to 46.8%. This degradation progressively flattens the current density-voltage characteristics near the maximum power point, leading to a decrease in power conversion efficiency from 13.23% to 8.25%. These quantitative trends establish clear benchmarks for interface engineering, indicating that surface passivation of the  N_iO_x layer is essential for suppressing transport barriers and achieving high fill factors. The model operates under steady-state conditions and does not account for ionic migration or capacitive effects, providing a foundation for future multiphysics extensions.