Water-Assisted Morphology and Crystal Engineering of Hybrid Organic-Inorganic Halide Perovskite: Implications for Optoelectronic Properties

The versatile application of hybrid organic-inorganic halide perovskites relies heavily on their crystal organization, which gives rise to distinct electronic structures. By manipulating the dimensionality and incorporating quantum confinement effects within the layered building blocks composed of n layers of [MX₆]⁴⁻ octahedra, the optoelectronic properties of lead halide perovskites can be further modulated. In this study, we present a water-assisted approach for the formation of microwires and 2D layered morphologies, achieved through a dissociation-recrystallization process using MAPbBr₃ microcubes. Along with a systematic alteration of the bandgap energy, our investigation uncovers variations in trap- and exciton-assisted recombination lifetimes, attributed to changes in exciton binding energy and structural confinement. Notably, the control of water and organic molecules within the precursor ionic solution plays a pivotal role, inducing or inhibiting growth and confining charge transport in specific directions, resulting in modified optical properties and exciton dynamics. This work sheds light on the significance of water-assisted methodologies and structural manipulation in hybrid organic-inorganic halide perovskites, providing a pathway towards advanced control and optimization of their optoelectronic characteristics.<br/><br/><b>Acknowledgments</b><br/>Financial support from FAPESP (grants no. 2022/06433-5, 2020/09563-1, and 2017/02317-2) and CEM-UFABC.