Ligand-mediated synthesis of compositionally related cesium lead halide CsPb2X5 nanowires with improved stability

Abstract

Compositionally related cesium lead halide materials, such as CsPb₂X₅, have attracted great interest due to their considerable optoelectronic/optical properties as well as improved stability. Currently, CsPb₂Br₅ nanocrystals can be well-designed by tuning the ligands or precursor ratio, whereas, CsPb₂X₅ (with Cl⁻ or I⁻) nanocrystals can only be obtained by the anion exchange method. Herein, we report a method to directly synthesize CsPb₂X₅ facilitated by thiol ligands. The morphology of CsPb₂X₅ can be designed as a nanowire. Importantly, the stability of directly synthesized CsPb₂X₅ nanowires is much improved when compared with the stabilities of the materials obtained by the anion-exchange method. We believe that this method will promote the application of 1D tetragonal CsPb₂X₅ in optoelectronics, optics and other fields.