Highly efficient electroluminescence from a heterostructure device combined with emissive layered-perovskite and an electron-transporting organic compound

Two PbI-based layered perovskite compounds, which possess cyclohexenylethylamine or phenylbutylamine as an organic ammonium layer, were newly found to exhibit efficient exciton emission due to their self-organized quantum well structure where a lead halide semiconducting layer and an organic ammonium dielectric layer are alternately piled up. We prepared heterostructure electroluminescent devices using the combination of the emissive layered perovskites and an electron-transporting oxadiazole. When the heterostructure devices were driven at 110 K, greenish emission, which corresponded well to the exciton emission, was observed. In the device using the perovskite with an organic layer of cyclohexenylethylamine, a high luminance exceeding 4000 ed m(-2) and high external EL quantum efficiency of 2.8% were attained at a current density of 50 mA cm(-2) at an applied voltage of 24 V.