Indium-assisted defect passivation engineering toward antisolvent-free high-performance and stable perovskite solar cells

Abstract Perovskite solar cells (PSCs) are currently recognized as the most competitive technologies in the photovoltaic industry. However, the power conversion efficiency (PCE) and stability of PSCs are significantly affected by various defects when synthesized via the antisolvent-free approach. Here, we report an effective defect passivation and perovskite crystal lattice regulation strategy by incorporating indium (III) chloride (InCl3) into the perovskite precursor solution. The smaller In3+ inserts interstitial sites and binds with the under-coordinated halide defects while releasing the micro strain of the perovskite lattice. Consequently, the long-lived carriers and higher quantum yield have been observed via the photoluminescence measurements. The incorporation of InCl3 significantly enhances the crystal structure stability under thermal, light, and moisture aging test conditions. Accordingly, the modified devices achieve a PCE of 24.43% on small-area modules and 21.19% on large-area modules (5 cm × 5 cm). The PCE of the InCl3-PSCs with an n–i–p planar structure maintains 80% initial efficiency after 378 h of maximum power point tracking.