Mixed Iodide-Bromide Methylammonium Lead Perovskite-based Diodes for Light Emission and Photovoltaics.

Vacuum deposition techniques are used to prepare mixed iodide–bromide methylammonium lead perovskite diodes via an intermediate double layer of the pure iodide and bromide perovskites. The diodes lead to bright electroluminescence, whose emission spectra maxima shift from the infrared toward the visible with increasing bromide content. When illuminated with AM1.5 simulated sunlight the devices function as efficient solar cells with power conversion efficiencies as high as 12.9%.