Highly efficient Cesium Titanium (IV) Bromide perovskite solar cell and its point defect investigation: A computational study

Lead-free, halide-based perovskites are drawing appreciable attention for solar cell applications due to the non-toxic nature and stable performance in ambient environment. In this study, we investigated different facets of a Cesium Titanium (IV) Bromide (Cs2TiBr6) perovskite solar cell (PSC) with ZnO and MoO3 as charge transport materials. Upon numerical optimization of perovskite layer thickness, its defect density, and the interface defect density, we propose a highly efficient, practically realizable PSC with a power conversion efficiency of 18.15%. Besides, we investigated different point defects in Cs2TiBr6 and the effect of their electronic band positions on the PSC performance. It is found that for Cs2TiBr6 based PSC applications, the material processing of Cs2TiBr6 is a crucial aspect and the PSC may underperform for deep defect states (0.2 eV similar to 1.6 eV) with defect density over 10(15) cm(-3). In addition, we analyzed different back contact materials and found that carbon-based back contact can be a low-cost solution to gold for Cs2TiBr6PSCs.

Automated summary

This study investigated a Cs2TiBr6 perovskite solar cell, optimized key parameters numerically, and proposed a highly efficient, practically realizable design with a power conversion efficiency of 18.15%. The research also emphasized the importance of Cs2TiBr6 material processing and the impact of back contact materials on PSC performance.