Perovskite/Organic Hybrid White Electroluminescent Devices with Stable Spectrum and Extended Operating Lifetime

We demonstrate a kind of perovskite/organic hybrid white electroluminescent device, where an ultrathin doping-free organic phosphorescent interlayer is embedded between a p-type hole transport layer and a n-type electron transport layer to give an organic p–i–n heterojunction unit, which is superimposed layer by layer onto a quasi-two-dimensional perovskite layer. The unique carrier transport character of the p-type hole transport layer leads to a broad carrier recombination region approaching the p–i–n heterojunction unit. As a result, pure-red emission from the perovskite layer and sky-blue emission from the organic p–i–n heterojunction were simultaneously achieved to generate white emission with a peak external quantum efficiency of 7.35%, Commission Internationale de L'Eclairage coordinates of (0.424, 0.363), and a low correlated color temperature of 2868 K. More importantly, excellent spectral stability and a greatly enhanced operating lifetime (10-fold longer than those of perovskite-only LEDs) are simultaneously achieved, providing a new path for the development of high-performance white LEDs.