From the perspective of luminescent materials, electroluminescence can be divided into non-electroluminescence and organic electroluminescence. Electroluminescent materials are generally such as semiconductor materials. Organic electroluminescent materials depend on the molecular weight of organic luminescent materials
It can be divided into small molecules and macromolecules. Organic dyes or pigments are used as light-emitting materials for small-molecule OLED materials, and conjugated or non-conjugated polymers (polymers) are used as light-emitting materials for polymer materials. PPV and its derivatives are typical high-molecular light-emitting materials.
Organic electroluminescent materials can be classified into HIL, HTL, EML, ETL, EIL and other materials according to the function and structure of OLED devices. Some of these luminous materials have the function of hole transport layer or electron transport layer. A small amount of Dopant organic fluorescence or phosphorescent dye in the layer of luminescent material can accept the energy transfer of the self-emitting body and emit different colors of light through the mechanism of carriertrap. Such doped luminescent material is usually called guest luminescent body or Dopant luminescent body, which is expressed in English as “Dopant”. From the perspective of luminescence principle, electroluminescence can be divided into high field electroluminescence and low field electroluminescence.
It can also be divided into thin film electroluminescent materials and dispersed electroluminescent materials