Researchers from MPI-P propose a new way to design efficient OLED materials without unipolar charge transport

Researchers from the Max-Planck-Institute for Polymer Research (MPI-P) have built upon new understanding on organic electronic material defects to suggest ways to design higher efficiency OLED materials.

 Charges in organic semiconductors, trapped by oxygen and water molecules (MPI-P)

The researchers explain that they have discovered that clusters of water inside organic semiconductors can function as hole traps, and oxygen clusters can capture electrons in hole-dominated organic semiconductors. Even a small number of such water and oxygen defects can cause highly unipolar charge transport and harm the efficiency of the materials.

Removing such defects in materials is very challenging - but the researchers propose a different path - designing the materials in such a way that the influence of water and oxygen molecules are reduced. Based on this concept, the first highly efficient OLEDs with defect-free electrical conduction have recently been realized.

Posted: Sep 25,2019 by Ron Mertens