Synthesis of a conjugated organic polymer could result in more efficient, cheaper electronics

21-Jul-10

Television and computer screens of the future could be brighter, clearer and more energy-efficient as a result of a process developed by a team of researchers from Canada and the Department of Energy's Oak Ridge National Laboratory. The synthesis of a conjugated organic polymer--widely used as a conductive material in devices like light-emitting diodes, televisions and solar cells--could mean more efficient, cheaper electronics. The group of scientists from ORNL and two Canadian universities outlined their success in growing highly structured short chains of polymer poly(3,4-ethylenedioxythiophene), or PEDOT. The theoretical expertise provided by ORNL scientists in synthesizing the PEDOT polymer could potentially have an impact on everyday electronic products. PEDOT is valued in electronic applications for the transparency, ductility and stability of its conducting, or doped, state. Because of its role as conductive material in organic light-emitting diodes, PEDOT is found in many electronic devices such as televisions and computer monitors. To create ordered arrays of the PEDOT polymer, the team placed a precursor molecule onto a copper crystalline surface, which helped to guide and initiate the polymerization reaction. This process is akin to placing eggs in an egg carton, where the free energy minima, or "indentations," in the copper surface allow the molecules to neatly stack next to each other to form a compact and organized polymer structure. By examining the polymer formation with the conventional means of scanning tunneling microscopy combined with the virtual microscopy, the team was able to clearly illustrate the construction and bonding of PEDOT arrays.