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Photovoltaic polymers: promising prospects

Conjugated polymers can exhibit electron–hole conduction similar to conventional semiconductors, an effect that is enhanced by chemical doping. Electrical currents are produced by separating the electron–hole pairs. This is done by forming interfaces between materials having different ionization potentials and electron affinities. Interfaces are created by superimposing layers of metals, inorganic oxides, and polymers, or by creating interpenetrating polymer networks. Although the best photovoltaic polymers produced so far are less efficient than their silicon counterparts, they produce much higher open-circuit voltages. Polymers are being developed that use dyes to increase light collection efficiency. Polymerization methods are being developed that increase the structural order, producing more efficient charge transport properties. Perhaps one day, you can convert the outside of your house into one big solar collector using photovoltaic polymer paint.

Acknowledgment
We are grateful for the continuing support of the Australian Research Council.

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Gordon G. Wallace is director of the Intelligent Polymer Research Institute (IPRI) at the University of Wollongong (NSW 2522, Australia; 61-2-4221 3127; fax 61-2-4221 3114; gordon_ wallace@uow.edu.au) and chair of the Electrochemistry Division of the Royal Australian Chemical Institute. He pioneered research into the development of intelligent polymer systems, and, with colleagues at IPRI, developed several new sensing, membrane-separations, controlled-release, and biomaterial technologies. He was awarded a QEII Fellowship in 1990, the inaugural Australian Polymer Science and Technology Achievement Award in 1992, and a five-year Australian Research Council Senior Research Fellowship in 1997; and he was the inaugural chair of the Asia Pacific Symposia on Intelligent Materials. He is a prolific author of scientific articles, books, and conference lectures. He received his Ph.D. from Deakin University (Victoria, Australia).

Paul C. Dastoor is a lecturer in the department of physics at the University of Newcastle (University Drive, Callaghan, NSW 2308, Australia; 61-2-4921 5426, fax 61-2-4921 6907; phpd@alinga.newcastle.edu.au). He received a B.A. degree in natural sciences from the University of Cambridge and his Ph.D. in surface physics from the University of Cambridge, where he studied the growth of thin films using helium atom scattering. His research interests encompass the growth and properties of thin polymer films, including the development of photovoltaic devices based on conducting polymers.

David L. Officer is an associate professor in chemistry at Massey University (IFS-Chemistry, Private Bag 11222, Palmerston North, New Zealand; 64-6-350 4796, fax 64-6-350 5682; d.officer@massey.ac.nz). He obtained his Ph.D. in organic chemistry from Victoria University, Wellington, New Zealand. He joined the staff at Massey University in 1986. He has active research programs in the synthesis and use of porphyrins for photovoltaic and molecular devices and the development of new organic-based intelligent materials usi

Chee O. Too is a senior fellow and assistant director of the Intelligent Polymer Research Institute (University of Wollongong, NSW 2522, Australia; 61-2-4221 3504, fax 61-2-4221 3114; chee_too@uow.edu.au). He received his Ph.D. in electrochemistry at Imperial College, London. He joined IPRI in 1990. His research interests include electrochemistry, conducting-multifunctional polymers, hydrogels, separation science (including membrane technology), and photovoltaics.