Accessing Highly Oriented Two-Dimensional Perovskite Films via Solvent-Vapor Annealing for Efficient and Stable Solar Cells
journal contributionposted on 09.11.2020, 18:33 by Xiaoming Zhao, Tianran Liu, Alan B. Kaplan, Chao Yao, Yueh-Lin Loo
Accessing vertical orientation of two-dimensional (2D) perovskite films is key to achieving high-performance solar cells with these materials. Herein, we report on solvent-vapor annealing (SVA) as a general postdeposition strategy to induce strong vertical orientation across broad classes of 2D perovskite films. We do not observe any local compositional drifts that would result in impure phases during SVA. Instead, our experiments point to solvent vapor plasticizing 2D perovskite films and facilitating their surface-induced reorientation and concomitant grain growth, which enhance out-of-plane charge transport. Solar cells with SVA 2D perovskites exhibit superior efficiency and stability compared to their untreated analogs. With a certified efficiency of (18.00 ± 0.30) %, our SVA (BDA)(Cs0.1FA0.9)4Pb5I16 solar cell boasts the highest efficiency among all solar cells with 2D perovskites (n ≤ 5) reported so far.
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SVA 2 D perovskites exhibitperovskite filmsBDAsolvent-vapor annealingsurface-induced reorientationexperiments point2 D perovskitesout-of-plane charge transportgrain growthpostdeposition strategyefficiency4 Pb 5Solar cellsStable Solar Cells AccessingOriented Two-Dimensional Perovskite...FAvapor plasticizing 2 D perovskite filmsSolvent-Vapor Annealing2 D perovskite films