Patch-healed grain boundary strategy to stabilize perovskite films for high-performance solar modules

The industrialization of organic-inorganic hybrid perovskite photovoltaic devices needs to be further promoted, while the efficiency and stability modules should be seriously considered. We have developed an on-surface conversion patch healing strategy for polycrystalline perovskite films via 1,3-diisopropyl-4,5-difluorobenzimidazolium iodide ion-based one-dimensional lead-iodide structure. Fluorine atom can interact with another benzimidazolium generating F···H hydrogen bond network to accelerate the charge extraction and transfer in intermolecular region. And, fluorine bonded with formamidinium (FA) ions and immobilized FA to improve the polycrystalline film durability. Attributed to the 1D structure stable chemical properties and specific electronic structure, the lab-scale device gained high efficiency of 24.05% in FACs-based perovskite system. The unsealed cell maintained 94.6% of its initial efficiency over 500 h under AM 1.5 G illumination in N2 atmosphere. And the large-area perovskite modules with high efficiencies (20.56% and 17.7% for the total areas of 36 cm2 and 100 cm2, respectively) fabricated by blade coating process, and the 1D-patch-based modules maintain 92.9% of the initial values after 2200 h of storage in 30% RH and 25 °C, which demonstrated the great application potential of this novel 1D patch healing in the perovskite photovoltaics.