Fabrication of high-efficiency perovskite solar cells and mini-modules by expanding the processing window with KSCN additive

Perovskite solar cells (PSCs) have garnered significant attention due to their high efficiency and low cost, making them a promising contender for the future of photovoltaic (PV) technology. Stable and controllable preparation of high-efficiency PSCs is crucial for the advancement of perovskite PV technology's industrialization. Herein, we demonstrate an additive-assisted blade-coating technique that boasts a wide air knife pressure window processing, making it ideal for the scalable deposition of perovskite films. KSCN was added to the perovskite precursor to induce an extra endothermic reaction, which effectively reduced the solvent evaporation rate, broadened the processing window, and slowed down the nucleation and crystallization process of the perovskite film. Moreover, the introduction of K+ led to the suppression of the formation of metal Pb0 and iodine vacancies in the film. Therefore, the high-quality perovskite films with full coverage, larger grains, higher crystallinity, fewer defects, as well as large-scale uniformity can be obtained under variable air knife pressure. As a result, power conversion efficiencies of 20.40% for small-area (0.07 cm2) blade-coated PSCs and 17.62% for perovskite solar modules with an active area of 10.00 cm2 were achieved. The proposed blade-coating technique with a wide processing window holds great potential for the commercialization of perovskite PV technology.