Unit-Cell Level Control and In-Situ Investigation of Ultrathin Perovskite Nanowires: New Fundamental Insights and Growth Mechanisms

With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Prof. Ou Chen of Brown University is studying how one-dimensional (1D) perovskite nanowires form and grow, with a focus on precisely controlling their size and quality. These tiny wire-shaped materials, made from perovskite semiconductors, have remarkable optical, electrical, and mechanical properties that make them promising building blocks for future technologies in optics, photonics, and electronics. By studying how different conditions affect the formation of these nanowires, the project aims to uncover the fundamental processes behind their growth. This knowledge will help scientists create high-quality nanowires in a more predictable and efficient way. The findings will advance the broader fields of nanochemistry and materials science and have potential implications for next-generation devices. In addition to its scientific impact, this project will include varied educational and outreach components. It will provide hands-on research and training opportunities for graduate and undergraduate students, helping to prepare future scientists and engineers. The project’s discoveries will also be shared with high school students and the general public through outreach programs such as Brown STEM Day and engaging video content on platforms like YouTube, helping to spark interest in nanotechnology and science more broadly. With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Prof. Ou Chen of Brown University is studying how to achieve atomic unit-cell-level control in the synthesis of ultrathin one-dimensional (1D) lead halide perovskite (LHP) nanowires (NWs), aiming to uncover the fundamental mechanisms underlying their growth. 1D semiconductor NWs exhibit unique properties—asymmetric quantum confinement, anisotropic optoelectronics, and mechanical flexibility—making them attractive for next-generation technologies. However, the ionic bonding nature of LHP nanomaterials causes rapid nucleation and growth, which limits mechanistic insights and synthesis precision of LHP NWs. The central hypothesis is that ultrathin perovskite NWs can be assembled from individual metal-halide octahedral units under mild and kinetically controlled conditions. By systematically investigating reaction parameters and employing a combination of ex situ and in situ characterization methods, this project will develop a reproducible synthetic strategy to fabricate ultrathin perovskite NWs with unit-cell-level thickness precision. The research will provide a generalizable framework for constructing environmentally friendly, lead-free double perovskite 1D nanostructures, and offer key insights into the anisotropic crystal growth of perovskite materials in general. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.