Rapid large-grain (>100 μm) formation of organic-inorganic perovskite thin films via shear deposition for photovoltaic application.

• High-speed (~5 mm·s−1) continuous solution-shearing method was introduced to fabricate the large grained (>100 μm) perovskite thin films and their photovoltaic devices. • Only 3.5 μL of perovskite precursor solution was consumed for 4.25 cm2 film so that this shearing deposition is more environmentally eco-friendly approach compared to the spin-coating. • The hydrophobic top plate enables to deposit more densely packed films with less void formation, consequently leading to the improved photovoltaic performance. High-speed continuous deposition of solution-processed perovskite thin films with controlled microstructural morphology has been intensively pursued toward practical commercialization of high-efficiency perovskite solar cells. In order to meet this urgent demand in a timely manner, we present a rapid (~5 mm·s−1) scalable meniscus-controlled coating method to deposit large-grained (>100 μm) perovskite thin films over large area. Shearing movement of the meniscus of perovskite solution, confined by the hydrophobic-treated top and temperature-controlled bottom plates enables a rapid crystallization of perovskite grains, also facilitating the continuous influx of solutes at the meniscus for continuous film growth with less consumption of perovskite solution. Optical and structural analyses revealed that the rapid-shear-deposited perovskite thin films possess a large-grained, densely-packed and highly-crystalline phase. Consequently, perovskite solar cell based this film exhibits the power conversion efficiency of 10.9% even without compositional engineering and additive controls. Therefore, it can be claimed that this rapid shearing deposition of perovskite solution paves a way to achieve a cost-competitive production of the high-efficiency solar cell. [ABSTRACT FROM AUTHOR]