Bright and fast-response perovskite light-emitting diodes with an ICBA:modified-C ₆₀ nanocomposite electrical confinement layer

Bright and fast-response CH₃NH₃PbBr₃ perovskite light-emitting diodes (PeLEDs) are realized by using ICBA:modified C₆₀ (MC₆₀) nanocomposites as the hole blocking layer (HBL) and electron transport layer (ETL). The photoluminescence spectrum shows that the use of hydrophilic MC₆₀ in the ETL helps the surface passivation of the perovskite layer. In addition, the photoelectron spectra and water-droplet contact angle images show that the use of the ICBA:MC₆₀ nanocomposite ETL can simultaneously confine the electrons and holes in the perovskite layer, which boosts the injected electron-hole radiative recombination efficiency and thereby increases the electroluminescence from 1 cd m^-2 to 2080 cd m^-2 at 6 V when the ICBA:3,5OEC₆₀ nanocomposite ETL is used. In addition, the operational frequency of the optimal PeLED is up to 1.5 MHz.