Highly Reproducible Fabrication of Perovskite Films with an Ultrawide Antisolvent Dripping Window for Large-Scale Flexible Solar Cells

摘要

Although perovskite solar cells (PSCs) have exhibited a high-power conversionefficiency, the reproducibility of high-quality perovskite films is still a big challengefor large-scale flexible devices. One reason is the super narrow antisolventdripping window, the other one is the difficulty in controlling the secondaryphases. Herein, 18C6 is introduced into the perovskite precursor to achieve ahigh-quality and reproducible large-scale (7 × 7 cm~2) flexible perovskite film byenlarging the antisolvent dripping window from 2 to 20 s, with an averageefficiency of 13.33% (best 15.80%). Moreover, from the in situ grazing-incidencewide-angle X-ray scattering result, the 2H phase perovskite is highly suppressedwith the additive of 18C6. The generality of the approach is also demonstrated inother antisolvents such as ethyl acetate. This finding provides an innovativesolution to the realization of repeatable, large-scale solution fabrication of PSCs.