Phase Behavior of Quasi-2D Hybrid Lead Bromide Perovskite Precursor Solutions

High Resolution Image Download MS PowerPoint Slide Over the past decade, the one-step antisolvent method called “solvent engineering” has been the most popular way to fabricate a lead halide perovskite thin film for optoelectronics. In this process, it is very important to understand the crystallization pathways from the precursor solution to the perovskite layer via a series of intermediates. However, the phase behavior of perovskite precursor solutions displaying all of this information was almost overlooked. Herein, we report the ternary phase diagram of a perovskite precursor solution composed of antisolvent (diethyl ether), solvents (DMF:DMSO), and quasi-2D perovskite (BA 2 FA n –1 Pb n Br 3 n +1, n → 1), in which BA and FA stand for n -butyl ammonium and formamidinium, respectively. To identify the phase boundary, the cloud points were measured as a function of composition. Here, p…