Green Anti-solvent Processed Efficient Flexible Perovskite Solar Cells

Flexible perovskite solar cells (PSCs) possess compatible features with low-cost, high throughput production approaches, showing great potentials in wearable, portable, flyable, and deployable applications. However, flexible PSCs with superior efficiency are commonly fabricated with an anti-solvent assisted crystallization (ASAC) method, which uses highly toxic solvents as the processed solvents. In this work, we use environmentally benign anti-solvents for the fabrication of flexible PSCs. Benefiting from the low-temperature solution processability of a high quality SnO₂ electron transport layer (ETL) with superior electron extraction and transfer features, flexible PSCs show an impressive PCE over 17% under reverse scan. This, to the best of our knowledge, is among the highest performances for flexible PSCs and is the first report for flexible PSCs fabricated by green anti-solvent processed techniques. These results provide new opportunities for environmental-friendly manufacturing of high performance flexible PSCs.