Modeling the performance of perovskite solar cells with inserting porous insulating alumina nanoplates

Peng et al. Science 379 683 (2023) reported an effective method to improve the performance of perovskite solar cells by using thicker porous insulator contact (PIC)-alumina nanoplates. This method overcomes the trade-off between the open-circuit voltage and the fill factor through two mechanisms: reduced surface recombination velocity and increased bulk recombination lifetime due to better perovskite crystallinity. From arguments of drift-diffusion simulations, we find that an increase in mobility and carrier recombination lifetime in bulk are the key factors for minimizing the resistance-effect from thicker PICs and achieving a maximum power conversion efficiency (PCE) at approximately 25% reduced contact area. Furthermore, the partially replacement of perovskite films with thicker PICs would result in a reduction in short-current density, but the relative low refractive index of the PICs imbedded into the high refractive index perovskite creates light trapping structures that compensate for this loss.