Fully Blade‐Coated Carbon Electrode Flexible Perovskite Solar Cells Using Green Solvents in Ambient‐Air

ABSTRACT Perovskite solar cells are undergoing scalable manufacturing and commercialized application, during which a convenient fabrication process is essential for the scalability of devices. Herein, we adopt blade coating and green solvents to fabricate each functional layer of carbon electrode flexible perovskite solar cells (C‐F‐PSCs) and modules in ambient air. To achieve C‐F‐PSCs with essential reliability and scalability, we select tetrahydrofurane (THF) to modulate the morphological and interfacial alignment of the organic buffer layer poly(3‐hexylthiophene‐2,5‐diyl) (P3HT), by adjusting its regioregular crystallinity, molecular ordering, and energy level alignment at the interface. The fully blade coated C‐F‐PSC delivers a state‐of‐the‐art conversion efficiency of 21.1% for a 0.09 cm 2 device under full light and 36.7% for 1 cm 2 device under 1000 LUX indoor light. The coated mini‐modules deliver an efficiency of 16.5% and 32.2% under standard fully light and indoor weak light, respectively, exhibiting an effective power source for the wearable electronics. The full blade coating of efficient devices in ambient air provides an appealing technique for upscaling, fast, and economic manufacturing of perovskite photovoltaics.