Light-emitting element, display device, and method for manufacturing light-emitting element

A light-emitting element, comprising:

• a first electrode;
• a second electrode;
• a light-emitting layer positioned between the first electrode and the second electrode, and containing a plurality of quantum dots and a first hole transport material;
• and
• a hole transport layer positioned between the first electrode and the light-emitting layer, and containing a second hole transport material, wherein:
• a solubility of the second hole transport material to a solvent, in which the plurality of quantum dots is soluble, is lower than a solubility of the first hole transport material to the solvent,
• a difference in ionization potential between the second hole transport material and the first hole transport material is smaller than a difference in ionization potential between the second hole transport material and the plurality of quantum dots,
• the first hole transport material contains a first polymer, the second hole transport material contains a second polymer, and the first polymer and the second polymer have a common repeating unit in a main chain,
• a weight-average molecular weight of the first polymer is smaller than a weight-average molecular weight of the second polymer, and
• the solvent is a nonpolar solvent having a dipole moment of 0.4 D or less.