Ultrathin Single-Helix Rare Earth Nanowires: Inorganic Analogues of RNA Conformation with High Mechanical Flexibility.

Abstract

Chirality has always been fascinating, yet inorganic chiral structures, especially those with helical shapes, are underexplored due to synthesis challenges. Herein, we regulated the conformation of rare earth ultrathin nanowires (RE NWs) at the sub-nanometer scale, constructing single-helix NWs (HNWs) with RNA-like conformation. The formation of HNWs is attributed to chiral ligands influencing the directional growth via steric hindrance at low temperatures. Based on this, 15 types of RE HNWs with helical structures were synthesized, demonstrating the strategy's universality. Notably, HNWs exhibit better flexibility than straight NWs, evidenced by their higher viscosity, lower glass transition temperature, shorter persistence length, and larger fractal dimension. This study provides a strategy for precise control of inorganic helical nanostructures and offers new insights into the chiral structure evolution.