Otto-Hahn-Medal for Oskar Sachnik

Oskar Sachnik, a former doctoral student at the Max Planck Institute for Polymer Research (MPI-P) in Prof. Paul Blom’s department, was awarded the Otto Hahn Medal by the Max Planck Society on June 17. The award was presented during the Max Planck Society’s annual meeting.

Oskar Sachnik, a former doctoral student in the department of Paul Blom, received the prestigious award for early-career researchers at the Max Planck Society’s annual conference in Frankfurt.

The Otto Hahn Medal is a major award for early-career researchers in Germany and is presented annually to recognize outstanding dissertations at the Max Planck Society’s research institutes. Since 1978, up to 30 young researchers have been honored each year for their excellent scientific achievements. The medal comes with a prize of 7,500 euros and is awarded at the Max Planck Society’s annual meeting.

Oskar Sachnik received the award for his outstanding dissertation at the Max Planck Institute for Polymer Research. He completed his dissertation, titled “Optimizing OLED performance through molecular engineering”, in December 2024 with the highest grade of summa cum laude, his work makes an important contribution to the further development of organic light-emitting diodes (OLEDs) through targeted molecular structure and material optimization.

The award-winning dissertation addresses a central challenge in OLED research that has persisted for decades. As early as the 1990s, the development of organic light-emitting diodes (OLEDs), which can be fabricated from solutions, sparked the vision of printed displays and, with them, the potential for drastically reduced manufacturing costs. However, this anticipated “revolution” was long in coming, as early, very simple OLED structures, consisting of only a single organic emissive layer between two electrodes, were not sufficiently efficient. This was primarily due to defects in the organic semiconductor layer, which led to energy loss.

To overcome these limitations, modern OLEDs are now often based on complex, vacuum-processed multilayer architectures with seven to eight functional layers and up to ten different organic materials in order to achieve the efficiency required for commercial applications. However, this structure is complex, costly, and poses a major obstacle to large-area printed OLED technologies.

Oskar Sachnik’s work addresses precisely this fundamental problem. He succeeded in achieving a decisive breakthrough in the fabrication of a defect-free organic semiconductor with a wide bandgap. This enabled him, for the first time, to create a single-layer OLED in which every injected electron is converted into a photon, corresponding to an internal quantum efficiency of 100%. Such a high efficiency in a single layer was previously considered unachievable in the OLED community.