Promoting solution-phase superlattices of CsPbBr3 nanocrystals. Academic Article uri icon

abstract

  • We present a size-selective method for purifying and isolating perovskite CsPbBr3 nanocrystals (NCs) that preserves their as-synthesized surface chemistry and extremely high photoluminescence quantum yields (PLQYs). The isolation procedure is based on the stepwise evaporation of nonpolar co-solvents with high vapor pressure to promote precipitation of a size-selected product. As the sample fractions become more uniform in size, we observe that the NCs self-assemble into colloidally stable, solution-phase superlattices (SLs). Small angle X-ray scattering (SAXS) and dynamic light scattering (DLS) studies show that the solution-phase SLs contain 1000s of NCs per supercrystal in a simple cubic, face-to-face packing arrangement. The SLs also display systematically faster radiative decay dynamics and improved PLQYs, as well as unique spectral absorption features likely resulting from inter-particle electronic coupling effects. This study is the first demonstration of solution-phase CsPbBr3 SLs and highlights their potential for achieving collective optoelectronic phenomena previously observed from solid-state assemblies.

published proceedings

  • Nanoscale

altmetric score

  • 1

author list (cited authors)

  • Mireles Villegas, N., Hernandez, J. C., John, J. C., & Sheldon, M.

citation count

  • 0

complete list of authors

  • Mireles Villegas, Noel||Hernandez, Josue C||John, Joshua C||Sheldon, Matthew

publication date

  • June 2023