Bright Blue Emitting Cu-Doped Cs₂ZnCl₄ Colloidal Nanocrystals.

ABSTRACT: We report here the synthesis of undoped and Cu-doped Cs₂ZnCl₄ nanocrystals (NCs) in which we could tune the concentration of Cu from 0.7 to 7.5%. Cs₂ZnCl₄ has a wide band gap (4.8 eV), and its crystal structure is composed of isolated ZnCl₄ tetrahedra surrounded by Cs⁺ cations. According to our electron paramagnetic resonance analysis, in 0.7 and 2.1% Cu-doped NCs the Cu ions were present in the +1 oxidation state only, while in NCs at higher Cu concentrations we could detect Cu(II) ions (isovalently substituting the Zn(II) ions). The undoped Cs₂ZnCl₄ NCs were non emissive, while the Cu-doped samples had a bright intragap photoluminescence (PL) at ∼2.6 eV mediated by band-edge absorption. Interestingly,

SUBMITTER: Zhu D 

PROVIDER: S-EPMC8016065 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature