Functional Materials for Organic and Plastic Electronics

Jean Fréchet, Program Leader

This program aims at the design and exploration of new electroactive materials and combinations of materials for organic or plastic electronics, the control of interfaces between electroactive materials, the determination of physical and functional properties, and the comparison of these properties with those of known materials to provide better understanding of the design rules and structure-property relationships for this important family of energy related materials. 
Four main areas of activity, each encompassing a major functional target, include:

• Fundamental studies and materials in photovoltaics

• Fundamental studies and materials in thin film transistors

• Fundamental studies and materials in light emitting diodes

• Use of 2-photon photoemission to study interfaces in electroactive materials

Thus, this activity is directed towards the study of a well-defined subset of electroactive organic/polymeric materials and nanocomposites obtained by their assembly.  The goal is to design and synthesize functional materials suitable for assembly or self-assembly via wet chemical processes with a high degree of ultimate control on many length scales simultaneously. The program also aims at gaining a fundamental understanding of processes that control function through interactions between materials in organic electronics. Experimental methods for the control of microstructure and morphology, particularly in thin films will be developed with the aid of scattering and a variety of microscopy tools including atomic force microscopy and transmission electron microscopy. A range of functional electroactive materials with potential for use in energy conversion, lighting and electronic devices will be studied.

CURRENT PROJECTS

• Materials for organic Solar Cells based on donor and acceptor polymers and copolymers. Understanding of electronic properties of polymer interfaces, self-organization into nanodomains; self-orientation, energy transfer processes between polymer components, effect of local dielectric constant, etc.  (J. Fréchet, C. Harris)
  

• Integrated self-assembled polymer monolayer-based Transistors with improved carrier mobility and switching characteristics  (J. Fréchet)
  

• Development of Light Emitting Diode technology including the design of optimized copolymer, dinuclear, hybrid morphologies for harvesting of both singlet and triplet excitons and intramolecular energy transfer and emission color; Self-organization of block copolymers into functional layered structures (J. Fréchet, R. Segalman)