Antisolvent-Assisted Growth of Centimeter-Scale CsPbBr$_3$ Perovskite Single Crystals: A Theory-Guided Approach

Abstract

The fabrication of large, high-quality single crystals (SCs) of all-inorganic cesium lead bromide (CsPbBr$_3$) via accessible methods remains a significant challenge. This work presents a systematic approach to optimize the antisolvent vapor-assisted crystallization (AVC) method, where the experimental design is guided by a theoretical methods at each step. A synergistic 9:1 (v/v) DMSO/DMF binary solvent was selected to balance solubility and kinetics, a choice rationalized by an analysis of Gutmann's donor numbers. Subsequently, ethanol was selected as a promising antisolvent by evaluating its properties against key criteria of miscibility and diffusion rate using Hansen Solubility Parameters (HSP) and Fick's law expressed in terms of saturated vapor pressure. Within this rationally-defined chemical system, the "growth window" was experimentally mapped, identifying an optimal precursor concentration of 0.35 M and a preliminary titration step to induce a controlled metastable state. The optimized protocol consistently yields phase-pure, orthorhombic CsPbBr$_3$ SCs up to 1 cm in size within one week at room temperature. The resulting crystals exhibit high crystallinity and thermal stability up to \SI{550}{\celsius}