Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Design Could Dramatically Boost Efficiency of Low-Cost Solar Panels

13.07.2015

X-ray Studies at SLAC’s Synchrotron Pave the Way for Better Methods to Convert Sunlight to Electricity

A new material design tested in experiments at the Department of Energy's SLAC National Accelerator Laboratory could make low-cost solar panels far more efficient by greatly enhancing their ability to collect the sun’s energy and release it as electricity.


UCLA

Scientists devised a new arrangement of solar cell ingredients, with bundles of polymer charge donors (green rods) and neatly organized spherical carbon molecules, also known as fullerenes or buckyballs, serving as charge acceptors (purple, tan). The researchers studied the new design at SLAC's Stanford Synchrotron Radiation Lightsource.

A team of University of California, Los Angeles, scientists found that by assembling the components of the panels to more closely resemble the natural systems plants use to tap the sun's energy, it may be possible to separate positive and negative charges in a stable way for up to several weeks compared to just millionths of a second – the current standard for many modern solar panels.

“In photosynthesis, plants that are exposed to sunlight use carefully organized nanoscale structures within their cells to rapidly separate charges – pulling electrons away from the positively charged molecule that is left behind, and keeping positive and negative charges separated,” said Sarah Tolbert, a UCLA professor of chemistry and one of the senior authors of the research. “That separation is the key to making the process so efficient.”

The team's X-ray studies at SLAC's Stanford Synchrotron Radiation Lightsource (SSRL), a DOE Office of Science User Facility, enabled them to see, at a microscopic level, which material design has the most ideal structure at the nanoscale for promoting this charge separation. The results are published in the June 19 edition of Science.

Plastic Panels Provide Low-cost Alternative to Silicon

To capture energy from sunlight, conventional rooftop solar cells use silicon, which can be expensive. Solar cells can also be made using lower-cost materials like plastics, but plastic cells are far less efficient -- in large part because the separated positive and negative charges in the material often recombine before they can become electrical energy.

“Modern plastic solar cells don’t have well-defined structures like plants do because we never knew how to make them before,” Tolbert said. “But this new system pulls charges apart and keeps them separated for days, or even weeks. Once you make the right structure, you can vastly improve the retention of energy.”

A Better Recipe for ‘Spaghetti and Meatballs’

The UCLA-developed system is composed of strands of a polymer, the building block of plastics, that absorb sunlight and pass electrons to a fullerene, a spherical carbon molecule also known as a “buckyball.”

The materials in these types of solar cells are typically organized like a plate of cooked pasta – a disorganized mass of long, skinny polymer “spaghetti” with random fullerene “meatballs.” But this arrangement makes it difficult to get current out of the cell because the electrons sometimes hop back to the polymer spaghetti and are lost.

The researchers figured out how to arrange the elements more neatly – small bundles of uncooked spaghetti with precisely placed meatballs. Some fullerene meatballs are designed to sit inside the polymer spaghetti bundles and others are forced to stay on the outside.

The fullerenes inside the structure take electrons from the polymers and toss them to the outside fullerenes, which can effectively keep the electrons separated from the polymer for weeks. A series of experiments at SSRL and other studies confirmed the best arrangement of the polymer strands and buckyballs.

Successes and Next Steps

“When the charges never come back together, it becomes easier to get them out of the solar cell in the form of electricity,” said Benjamin Schwartz, a UCLA professor of chemistry and a co-author of the study. “This is the first time such long charge lifetimes have been shown using this type of material.”

Researchers found that the materials self-assemble into this ordered form when placed in close proximity. The new design is also more environmentally friendly than current technology, because the materials can assemble in water instead of more toxic organic solutions that are typically used.

“Once you make the materials, you can dump them into water and they assemble into the appropriate structure because of the way the materials are designed,” Schwartz said.

The researchers are now working on how to incorporate the technology into actual solar cells, and Tolbert said the team is planning follow-up research at SSRL.

The work was supported by the National Science Foundation and the U.S. Department of Energy, and the DOE Office of Biological and Environmental Research.

This report was adapted from a press release by the University of California, Los Angeles. View the original release here.

SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, Calif., SLAC is operated by Stanford University for the U.S. Department of Energy's Office of Science. For more information, please visit slac.stanford.edu.

SLAC National Accelerator Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

Andrew Gordon | newswise

More articles from Power and Electrical Engineering:

nachricht Energy hybrid: Battery meets super capacitor
01.12.2016 | Technische Universität Graz

nachricht Tailor-Made Membranes for the Environment
30.11.2016 | Forschungszentrum Jülich

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>