Scalable Fabrication of Efficient Perovskite Solar Modules on Flexible Glass Substrates

Perovskite materials are good candidates for flexible photovoltaic applications due to their strong absorption and low-temperature processing, but efficient flexible perovskite modules have not yet been realized. Here, a record efficiency flexible perovskite solar module is demonstrated by blade coating high-quality perovskite films on flexible Corning Willow Glass using additive engineering. Ammonium chloride (NH₄Cl) is added into the perovskite precursor solution to retard the nucleation which prevents voids formation at the interface of perovskite and glass. The addition of NH₄Cl also suppresses the formation of PbI₂ and reduces the trap density in the perovskite films. The implementation of NH₄Cl enables the fabrication of single junction flexible perovskite solar devices with an efficiency of 19.72% on small-area cells and a record aperture efficiency of 15.86% on modules with an area of 42.9 cm². This work provides a simple way to scale up high-efficiency flexible perovskite modules for various applications.