Light emitting device including tandem structure

A light emitting device comprising:

• a pair of electrodes;
• two or more light emitting elements disposed between the electrodes in a stacked arrangement, wherein each of the two or more light emitting elements comprises a layer comprising an emissive material, and wherein the emissive material included in each of the two or more light emitting elements comprises quantum dots;
• and
• a charge generation element disposed between adjacent light emitting elements in the stacked arrangement, the charge generation element comprising a first layer comprising nanoparticles of an inorganic n-type semiconductor material and a second layer comprising a hole injection material, where the nanoparticles of the inorganic n-type semiconductor material are in direct contact with at least one layer of the emissive material.