Project R-13033

On the chemical origin of intrinsic performance limits of organic electronics. (Research)

The performance level of organic electronic devices like photovoltaics (OPVs) and photodetectors (OPDs) has increased steadily over the past decades (PCE of 18%/D* of 10E14 Jones). In the meanwhile, it has also become clear that their theoretical performance limits (Shockley-Queisser limit/background limited infrared photodetection) are not significantly different with respect to their inorganic counterparts. Further increasing the performance is possible, but will crucially depend on a more profound understanding of the fundamental physical principles and limitations. An eminent, yet unresolved problem in this respect is the batch-to-batch variation of the state-of-the-art alternating push-pull donor copolymers used as photo-active materials in OPVs and OPDs, resulting in inconsistent performance levels. In this project, the limitations of these devices, possibly caused by polymer imperfections (such as homocoupling, end-capping, chain length variation, and polydispersity), are studied from a fundamental materials chemist point of view. The general aim is to elaborate on the origin of material and device limitations. The project not directly targets to increase the performance level of OPVs and OPDs but aims at a better fundamental understanding of the scientific concepts underlaying it. More in particular, by synthesizing 'defect-free' semiconducting polymers in a controlled manner, the effect of donor polymer imperfections on the device performance will be investigated.

01 October 2022 - 30 September 2025