Narrow Emission from Rb3Sb2I9 Nanoparticles

Abstract

AbstractMetal halide perovskites have gained attention for their optoelectronic properties and are employed as the active layer in solar cells, light‐emitting diodes, and photodetectors. However, the use of lead in the best‐performing perovskite devices may limit their wider application. Prior reports of lead‐free perovskite nanoparticles have exhibited linewidths more than twice as wide as their lead‐halide counterparts, limiting their attainable color gamut. Here the solution synthesis of lead‐free Rb3Sb2I9 nanoplatelets and single crystals is reported; the single crystals exhibit broad (full‐width at half‐maximum (FWHM) = 75 nm) photoluminescence centered at 635 nm, while the nanoplatelets exhibit narrow emission (FWHM = 21 nm) at 512 nm. The photoluminescence quantum yield of both the single crystals and nanoplatelets is low and the present demonstration of the narrowest emission among all lead‐free perovskites reported to date motivates further study of how these and related materials can achieve further‐enhanced brightness.