This project aims to continuously manufacture ultra-stable monodispersed perovskite nanoparticles for applications in white light-emitting diodes (LEDs). A conventional microfluidic flow reactor, used for continuous production of nanoparticles, is not a generalizable approach and requires specific experimental conditions for the growth of specific nanoparticles, and often results in non-uniformity in the size and shape of the nanoparticles as well as their undesirable aggregation. This award supports fundamental research for the development of a robust process that combines two types of reactors, block copolymer-based nanoreactors and a flow microreactor. This process provides a unique environment and capability for manipulating the reaction of precursors within the nanoreactors inside the flow microreactor, which, in turn, yields multifunctional nanoparticles in a predictable and continuous manner. These nanoparticles can be exploited either individually or as building-blocks for the bottom-up assembly of nanostructured materials and devices with desirable characteristics for use in energy and biomedical applications, thereby translating fundamental scientific discoveries into useful technologies that benefit society. Knowledge generated by this project broadly impacts the development of robust strategies for continuous production of a rich variety of monodispersed, ultra-stable, multifunctional nanoparticles, not limited to perovskite nanoparticles, with precisely controlled dimensions and surface chemistry. This project gives opportunities to graduate, undergraduate and high school students, including women and underrepresented minorities, to be exposed to nanocrystal, nanoscience and nanomanufacturing research.
Specifically, green- and red-emitting cesium lead bromide and iodide nanoparticles are selected as perovskite nanoparticles in this study motivated by their intriguing optical properties. These nanoparticles are continuously crafted by capitalizing on rationally designed star-like block copolymers as nanoreactors inside a flow microreactor. This process imparts the scalable nanomanufacturing of perovskite nanoparticles with high uniformity and superior stabilities via a double protection, that is, direct capping with inorganic silica shell followed by hydrophobic organic silicone shell. This research fills the knowledge gap on the thorough understanding of the formation mechanism of uniform perovskite nanoparticles in a continuous-flow microreactor. The research team plans to design nanoreactors based on amphiphilic star-like block copolymers with well-defined molecular weights, manufacture a large amount of monodisperse ultra-stable perovskite nanoparticles of different compositions, explore the stabilities of silicone-capped and silica-protected core/shell nanoparticles, and fabricate high performance white LEDs using the perovskite nanoparticles.
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.