Inverted quantum-dot light emitting diodes with cesium carbonate doped aluminium-zinc-oxide as the cathode buffer layer for high brightness

We report an inverted structure of quantum-dot light emitting diodes (QLEDs) with cesium carbonate (Cs₂CO₃) doped aluminum-zinc-oxide (AZO) as the cathode buffer. The Cs₂CO ₃ doped AZO with Cs₂CO₃ blending ratios (AZO:Cs₂CO₃) from 4:1 to 2:1 was used as an electron transport layer in QLEDs. It is found that the conductivity of the AZO:Cs ₂CO₃ blended solution increases with the increase in the concentration of Cs₂CO₃ until a particular concentration, and the luminance intensity increases sharply from 9949 to 57 350 cd m ^-2. It is concluded therefore that Cs₂CO₃ doped AZO could be a good cathode buffer for inverted QLEDs.