Conductive polymer brushes: New electro- and photo- active molecular architectures

• Applicants: Professor Dr. Karl Leo; Professor Dr. Manfred Stamm
• Subject Area: Experimental and Theoretical Physics of Polymers
• Term: from 2005 to 2009
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 13245752

The project aims at the development of new techniques to manufacture stable conductive polymer layers, where chains are tethered to the substrate or particle by one (end)point (conductive polymer brushes, CPBs). The molecules will be locally fixed and stabilized, while their conformation, dynamics and other important properties (optical, electronic) will resemble the properties of the parent non-immobilized CPs. We first will focus an synthesis of CPBs of different types, including multicomponent brushes. For this we will adapt different routes known for CPs to the synthesis of CPBs. CPBs will be grown onto surfaces of different chemical composition and geometry (including nanoscopic particles). We will study and optimize fundamental properties of CPBs, such as self-assembly, optical, electrical, redox properties and wetability. Moreover, we will investigate how to switch those properties under external stimuli (such as environment, temperature, electric field, etc.) and explore the possibility to utilize CPBs as active layers in organic solar cells (OSCs). The following architectures of the active layers of OSCs will be explored: (a) CP brushes of electron-donor materials, such as polyalkylthiophenes (or low band gap conductive copolymers) grown on an electrode and then saturated (swollen) with electron-acceptors, such as fullerene derivatives; (b) CPBs grown on inert nanoparticles ( hairy nanoparticles ) and then blended with an electron acceptor material. We expect to obtain interesting new thin conducting polymer films with largely improved properties, which can be used for photo-voltaic or sensor applications.

• DFG Programme: Research Grants
• Participating Persons: Dr. Anton Kiriy; Dr. Martin Pfeiffer