Multiscale Chiral Synthesis via Self-Assembly of Achiral Nanoparticles for Next-Generation Chiral Material-Based Applications: The Role of Metal Ions as Chirality Messengers

Abstract

Chiroptical activity over a broad range is expected to enable numerous applications including bioimaging and nanothermometers. However, understanding the chemical mechanism behind producing multiscale chirality for broad range chiroptical activities remains challenging. Here, we present a simple multiscale chiral synthesis and elucidate the underlying chemical mechanism for the self-assembly of achiral copper sulfide nanoparticles (NPs). The initially achiral NPs assemble into anisotropically twisted structures with a distinct handedness depending on the chirality of the molecules in the solution. Importantly, we reveal for the first time, to our knowledge, that metal ions act as messengers that transfer chirality information from small molecules to microstructures. The resulting multiscale chiral structures exhibit strong and broad chiroptical activities ranging from the ultraviolet to the infrared. This study not only enhances the understanding of the mechanism of chiral self-assembly but also offers effective approaches to producing chiral inorganic materials with strong chiroptical activities for next-generation chiral material-based applications.