Organic light emitting diode for high efficiency

An organic light-emitting diode, comprising:

• a first electrode;
• a second electrode opposite the first electrode;
• and
• a light-emitting layer, an electron-density-controlling layer, an electron transport layer and an electron injection layer in that order between the first electrode and the second electrode,
• wherein
• the light-emitting layer includes a host and a dopant,
• the electron-density-controlling layer is materially different from the electron transport layer;
• the electron transport layer is materially different from the electron injection layer;
• and the electron injection layer is materially different from the second electrode,
• an affinity of the host of the light-emitting layer (Ah), an affinity of the electron-density controlling layer (Aed), and an affinity of the electron transport layer (Ae) satisfy a relationship of Ah>Aed>Ae,
• the material of the electron-density-controlling layer is greater in electron mobility than that of the electron transport layer,
• the electron-density-controlling layer includes at least one selected from among compounds represented by the following Chemical Formulas A and C, and at least one anthracene compound represented by the following Chemical Formula H is used as the host:
• wherein,
• in Chemical Formula A and Chemical Formula C,
• R1 to R8 and R31 to R38 may be the same or different, and are each independently any one selected from among a hydrogen atom and a deuterium atom,
• R11 to R17 and R41 to R47 may be the same or different, and are each independently any one selected from among a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl of 1 to 30 carbon atoms, a substituted or unsubstituted aryl of 6 to 50 carbon atoms, and a substituted or unsubstituted heteroaryl of 2 to 50 carbon atoms containing O, N or S as a hetero atom,
• Ar1 and Ar2 may be the same or different, and are each independently a deuterium substituted phenyl, and a linker L is an unsubstituted naphthylene of 10 carbon atoms,
• wherein,
• the substituents R61 to R65 may be the same or different, and are each independently any one selected from among a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl of 1 to 30 carbon atoms, a substituted or unsubstituted aryl of 6 to 50 carbon atoms, a substituted or unsubstituted heteroaryl of 2 to 50 carbon atoms containing O, N or S as a hetero atom, with the proviso that a hydrogen atom is positioned on each of the aromatic ring carbon atoms to which none of the substituents R61 to R65 are bonded,
• the linker L′ is a single bond,
• j is 1,
• k is an integer of 1 to 5,
• l to n may be the same or different, and are each independently an integer of 1 to 4,
• o is an integer of 1 to 3, with the proviso that when each of k to o is 2 or greater, corresponding R61's to R65's may be the same or different,
• ‘***’ for moiety X denotes a bonding site for bonding L′,
• with the proviso that the anthracene compound of Chemical Formula H used in the light-emitting layer is different from the compounds of [Chemical Formula A] and [Chemical Formula C] used in the electron-density-controlling layer,
• wherein the term ‘substituted’ in the expression ‘substituted or unsubstituted’ means having at least one substituent selected from the group consisting of a deuterium atom, an alkyl of 1 to 24 carbon atoms, an aryl of 6 to 24 carbon atoms, and a heteroaryl of 2 to 24 carbon atoms.