UCLA chemists published a study Friday about a solar-cell technology they developed using plastic materials. The new system improves how solar cells capture and retain energy from the sun.
After absorbing light energy during photosynthesis, plant cells separate positively charged molecules from negatively charged electrons. Like plants, the UCLA solar-cell technology also separates charges for up to weeks at a time.
Previous solar cells consisted of an arrangement of molecules called organic photovoltaics, according to Phys.org. Molecules called polymer donors would absorb sunlight energy, then pass their electrons to molecules called fullerene acceptors. In these systems, however, positive and negative charges frequently recombined before they could be converted to electrical energy. Electrons accepted by the fullerene acceptors would return to the polymer and disappear, instead of being stored for energy.
UCLA’s new system organizes photovoltaic components into bundles, with fullerene molecules sprinkled inside and outside the polymer material. Now, fullerene molecules within the polymer bundle toss electrons to fullerene molecules outside. This method separates the electrical charge for weeks, according to the study.
Yves Rubin, a senior author of the study, said this photovoltaic technology may be a cheaper option in the future since silicon, a component of many rooftop solar panels, is expensive to manufacture.
“We’re continuing our work in making (our technology) into practical devices,” said Rubin, an associate professor of chemistry at UCLA. “You can make (silicon solar cells) easily, but it takes a lot of energy.”