Photovoltaic organic polymer advance made

SANTA BARBARA, Calif., Oct. 19 (UPI) -- U.S. scientists report a major advance in synthesizing photovoltaic organic polymers that convert sunlight into electricity in non-silicon-based solar cells.

University of California-Santa Barbara Professor Guillermo Bazan and colleagues said they've been able to reduce reaction time by 99 percent, while more than tripling the average molecular weight of the polymers.

The scientists said the reduced reaction time effectively cuts production time for the organic polymers by nearly 50 percent, since reaction time and purification time are approximately equal in the production process, in both laboratory and commercial environments.

The higher molecular weight of the polymers increases current density in plastic solar cells by as much as a factor of more than four, a major benefit, the researchers said.

The methodology "will greatly accelerate research in this area," Bazan said, "by making possible the rapid production of different batches of polymers for evaluation.

"We plan to take advantage of this approach both to generate new materials that will increase solar cell efficiencies and operational lifetimes, and to reevaluate previously-considered polymer structures that should exhibit much higher performance than they showed initially."

The research appears in the early online edition of the journal Nature Chemistry.