Alan J. Heeger, Conductive Polymers, and Plastic Solar Cells
After receiving 'his physics Ph.D. at the University of California at Berkeley in 1961, [Alan J.] Heeger would spend the next 20 years teaching the subject at the University of Pennsylvania – while also designing and then launching one of the nation's premiere scientific think tanks: the Laboratory for Research on the Structure of Matter.
It was there in the Penn experimental lab, during the fall and early winter of 1976, that Heeger and two colleagues would first begin to explore the possibility of manipulating "long chains of polymers" with an eye to "altering their properties" so that they could be coaxed into conducting electricity.'1
The 2000 Nobel Prize in Chemistry honors Dr. Heeger, Alan G. MacDiarmid, and Hideki Shirakawa for their 'discovery that plastics, or polymers, can be made to conduct electricity much like metals. This finding turned on its head the conventional wisdom that polymers could not conduct electricity, and unleashed a flurry of new research among physicists, chemists, and materials scientists worldwide.
Polymers are molecular chains with a regularly repeating structure. For a polymer to conduct electric current, it must consist alternately of single and double bonds between the carbon atoms. It must also be "doped," which means that electrons are removed (through oxidation) or introduced (through reduction). These "holes," or extra electrons, can move along the molecule, making it electrically conductive.
Drs. MacDiarmid, Heeger, and Shirakawa were responsible for the 1977 synthesis and the electrical and chemical doping of polyacetylene, the prototypical conducting polymer, and the rediscovery of polyaniline, now the foremost industrial conducting polymer.'
Heeger has recently conducted research in 'the development of low-cost, highly efficient plastic solar cells … . The cells, made from organic materials, exhibit the highest energy-conversion rating for such devices. … [Heeger sees] the discovery of ultrafast photo-induced electron transfer as the foundation of a technology for low-cost solar cells.'2
1 Edited excerpts from University of Pennsylvania's Alan G. MacDiarmid and Former Penn Physicist Alan J. Heeger are Among Three Winners of the 2000 Nobel Prize in Chemistry
2 Edited excerpts from Frontiers of Science Lecture: Low-cost Plastic Solar Cells
Additional information about Alan Heeger, conductive polymers, and plastic solar cells is available in electronic documents and on the Web.
One-Dimensional Phonons and "Phase-Ordering" Phase Transition in Hg3-deltaAsF6, Physical Review Letters Vol. 39, Issue 23: 1484-1487; December 5, 1977
Electrical Conductivity in Doped Polyacetylene, Physical Review Letters Vol. 39, Issue 17:1098-1101; October 24, 1977
with equation correction, Physical Review Letters Vol. 40, Issue 22:1472; May 29, 1978
Subgap Absorption in Conjugated Polymers; DOE Technical Report; 1991
Measurements of Photo-induced Changes in Conjugated Polymers; DOE Technical Report; 1991
Additional Web Pages:
Center for Polymers and Organic Solids, co-established by Alan Heeger, UC Santa Barbara
OPN Talks with Alan J. Heeger, Optics and Photonics News
Nobel Lecture by Alan Heeger, nobelprize.org (video)
Interview with Alan Heeger, Alan G. MacDiarmid and Hideki Shirakawa, nobelprize.org (video)
Alan Heeger - Science Video Interview, Vega.org (video)
Next Generation Solar Cells; Production and Storage: Toward a More Efficient Use of Renewable Energy Sources (video)
Low Cost “Plastic” Solar Cells; Emerging Energies Technology Summit 2007: Session Two: Renewable Energy and the Hydrogen Economy, Program 1 (video)