TY - GEN A1 - Kodalle, Tim A1 - Malekshahi Byranvand, Mahdi A1 - Goudreau, Meredith A1 - Das, Chittaranjan A1 - Roy, Rajarshi A1 - Kot, Małgorzata A1 - Briesenick, Simon A1 - Zohdi, Mohammadreza A1 - Rai, Monika A1 - Tamura, Nobumichi A1 - Flege, Jan Ingo A1 - Hempel, Wolfram A1 - Sutter‐Fella, Carolin M. A1 - Saliba, Michael T1 - An integrated deposition and passivation strategy for controlled crystallization of 2D/3D Halide Perovskite films T2 - Advanced Materials N2 - This work introduces a simplified deposition procedure for multidimensional (2D/3D) perovskite thin films, integrating a phenethylammonium chloride (PEACl)‐treatment into the antisolvent step when forming the 3D perovskite. This simultaneous deposition and passivation strategy reduces the number of synthesis steps while simultaneously stabilizing the halide perovskite film and improving the photovoltaic performance of resulting solar cell devices to 20.8%. Using a combination of multimodal in situ and additional ex situ characterizations, it is demonstrated that the introduction of PEACl during the perovskite film formation slows down the crystal growth process, which leads to a larger average grain size and narrower grain size distribution, thus reducing carrier recombination at grain boundaries and improving the device's performance and stability. The data suggests that during annealing of the wet film, the PEACl diffuses to the surface of the film, forming hydrophobic (quasi‐)2D structures that protect the bulk of the perovskite film from humidity‐induced degradation. KW - 2D/3D perovskites KW - crystallization KW - in situ characterization KW - stability Y1 - 2024 U6 - https://doi.org/10.1002/adma.202309154 SN - 0935-9648 VL - 36 IS - 24 PB - Wiley CY - Weinheim ER -