Blue perovskite light-emitting diodes based on RbX-doped polycrystalline CsPbBr3 perovskite films

The RbX-incorporated CsPbBr₃ perovskite films remarkably increases the bandgap and realizes pure blue emission. The corresponding RbBr-doped and RbCl-doped CsPbBr₃ PeLEDs demonstrate efficient blue emission with EL peaks located at 492 nm and 468 nm, respectively.