Retarding Ion Migration for Stable Blade-Coated Inverted Perovskite Solar Cells

The fabrication of perovskite solar cells (PSCs) through blade coating is seen as one of the most viable paths toward commercialization. However, relative to the less scalable spin coating method, the blade coating process often results in more defective perovskite films with lower grain uniformity. Ion migration, facilitated by those elevated defect levels, is one of the main triggers of phase segregation and device instability. Here, a bifunctional molecule, p-aminobenzoic acid (PABA), which enhances the barrier to ion migration, induces grain growth along the (100) facet, and promotes the formation of homogeneous perovskite films with fewer defects, is reported. As a result, PSCs with PABA achieved impressive power conversion efficiencies (PCEs) of 23.32% and 22.23% for devices with active areas of 0.1 cm2 and 1 cm2, respectively. Furthermore, these devices maintain 93.8% of their initial efficiencies after 1 000 h under 1-sun illumination, 75 degrees C, and 10% relative humidity conditions. A bifunctional molecule, p-aminobenzoic acid (PABA), increases ion migration barrier, induces (100) facet perovskite grain growth, and yields defect-reduced, homogeneous films. The blade-coated PABA-based inverted PSC achieves an impressive PCE of 23.32% and maintains 93.8% of its initial efficiency after 1000 hours under 1-sun illumination at 75 degrees C and 10% relative humidity.image

Automated summary

The fabrication of perovskite solar cells through blade coating often leads to more defective films. In this study, a bifunctional molecule, p-aminobenzoic acid (PABA), was used to enhance the barrier to ion migration and promote the formation of defect-reduced, homogeneous films. The PSCs with PABA achieved impressive power conversion efficiencies and maintained high stability under extreme conditions.