Effect of a Rubidium Chloride Carrier Confinement Layer on the Characteristics of CsPbBr 3 Perovskite Light-Emitting Diodes.

This work describes the effect of a rubidium chloride (RbCl) interlayer in CsPbBr 3 perovskite light-emitting diode (LED) structures. RbCl crystallites exhibited polyhedral structures and lattice parameters similar to those of CsPbBr 3 perovskite crystallites. The lattice mismatch between the RbCl interlayer and CsPbBr 3 active layer was only approximately 2%. The devices exhibited the best quality and performance when RbCl was used as the nucleation and carrier confinement layer. The crystallite sizes of CsPbBr 3 with 0.2-, 0.5-, and 1-nm-thick RbCl bottom layers were 55.1, 65.4, and 55.1 nm, respectively. The full width at half maximum (FWHM) of the photoluminescence (PL) emission peak for CsPbBr 3 with the RbCl bottom layer was 0.096 eV.