| abstract |
The present invention is directed to matrix compounds and an organic light-emitting diode (OLED) comprising an emission layer and an electron transport layer stack of at least two electron transport layers, wherein a first electron transport layer and a second electron transport layer comprises at least one matrix compound, wherein the matrix compound or compounds of the first electron transport layer is/are different to the matrix compound or compounds of the second electron transport layer; and in addition, the first electron transport layer comprises a dopant of a lithium halide and/or lithium organic complex; and the second electron transport layer is free of a dopant; wherein at least one matrix compound of the second electron transport layer having the chemical formula Ia, Ib and/or Ic: (Ia) (Ib) (Ic) wherein Ar=substituted or unsubstituted arylene with 6 to 20 ring-forming carbon atoms; or carbazolylene; ET=substituted or unsubstituted aryl group with 13 to 40 ring-forming carbon atoms; or a substituted or unsubstituted heteroaryl group with 14 to 40 ring-forming atoms. |