Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Research on thin-film solar cells heats up at UC Santa Cruz

Sue Carter in her lab. Credit R. Jones.
Sue Carter in her lab. Credit R. Jones.

Abstract:
Sue Carter, a professor of physics at the University of California, Santa Cruz, is pursuing a variety of strategies to develop cheaper and more efficient solar cells. She was awarded five new grants this year totaling more than $1 million to fund her research on new materials and technologies for solar energy.

Research on thin-film solar cells heats up at UC Santa Cruz

Santa Cruz, CA | Posted on November 2nd, 2010

Carter's research focuses on lowering the cost of solar cells and reducing the energy "payback time"--how long it takes a solar cell to generate the amount of energy that was used to manufacture it. Her lab uses thin-film technologies and printable semiconductor materials that enable the production of solar cells using less material and less energy compared to standard manufacturing processes.

While a growing number of companies are now making thin-film solar cells, conventional silicon-based cells still account for the vast majority of photovoltaic systems in use today. Silicon is a cheap and abundant material, but getting the purity and crystalline structure needed for solar cells requires energy-intensive processing at very high temperatures. And silicon cells have to be thick, because silicon does not absorb light very well.

Thin-film solar cells use much less material than silicon cells and offer advantages such as light weight and the potential to deposit them on flexible substrates. Cadmium telluride (CdTe) is currently the leading thin-film material, used in solar cells produced by several companies. But tellurium is one of the rarest elements in the world, which could limit the long-term viability of CdTe cells in the solar energy market. Carter's lab has developed a procedure for making ultrathin CdTe solar cells using cheaper processing and only about 10 percent of the material needed to make standard CdTe cells.

"We do the processing under normal temperatures and pressures, so it uses a lot less energy than vacuum-based processing," Carter said. "And we were able to cut the thickness down from three microns to about 360 nanometers and still get good power efficiencies, so the amount of material you need is almost an order of magnitude less."

These results were reported in a recent paper in Applied Physics Letters (published online on June 15, 2010). Carter's ongoing research to extend this work is funded by a new grant from the California Energy Commission's Energy Innovations Small Grant Program. One of the goals is to deposit the ultrathin CdTe film on a cheap, flexible substrate to make the solar cells more portable, she said.

Carter's lab is also working to develop thin-film solar cells that use cheaper, more abundant materials than CdTe and the other leading thin-film material, copper indium gallium selenide (CIGS). The indium in CIGS cells is almost as rare an element as tellurium.

"If we want to scale up solar energy production to terawatt volumes, we need to use more abundant materials," Carter said.

Alternative thin-film materials being studied in Carter's lab include lead sulfide and copper sulfide. In another recent paper in Applied Physics Letters (published online on July 28, 2010), she and her co-workers reported high efficiency at low temperature in solar cells using lead sulfide and titanium dioxide nanoparticles (semiconductor crystals with dimensions of a few nanometers). This approach makes use of quantum properties of lead sulfide nanoparticles that could, in theory, enable solar cells to achieve much higher efficiencies than current solar technologies. Ongoing work in this area is funded by a National Science Foundation grant for a collaborative effort involving researchers at UCSC, UC Davis, and industry partners.

A separate NSF grant is funding Carter's research on copper-based materials for thin-film solar cells. This work is motivated by concerns about the toxicity of cadmium, lead, and other materials used in thin-film solar cells.

Finally, a Department of Energy grant and an industry grant from Abengoa Solar are funding Carter's work on luminescent solar concentrators. This technology can be used to capture sunlight over a large area and concentrate its energy on a smaller area of solar cells. Many types of dyes, polymers, and other materials can absorb sunlight and then fluoresce, re-emitting the light in a different wavelength. In a luminescent solar concentrator, the fluorescent material is incorporated into a thin, flat sheet. The re-emitted light is guided to the edge of the sheet by "total internal reflection," the same phenomenon that moves light pulses through fiber-optic cables. Solar cells arrayed along the edges convert the light to electricity.

"One of the nice things about this is that the material can be transparent--it looks like a darkened window. So you can integrate the luminescent solar concentrator and the solar cells into the windows of a building," Carter said. "It's also very cheap material, so you're using a less expensive material to collect the sunlight, and that reduces the amount of expensive solar cells you need."

Enclosing the film between plates of glass in a water- and oxygen-free environment can prevent degradation of the luminescent material over time, she said.

Carter's collaborators on these projects include Glenn Alers, adjunct professor of physics; Frank ("Bud") Bridges, professor of physics; industry partners at Abengoa, Add-Vision, and Solexant; and a large number of postdoctoral researchers and graduate and undergraduate students.

In addition to her lab on campus, Carter and Alers direct the Laboratory for Solar Energy and Renewable Fuels (SERF) at the Advanced Studies Laboratories, a UCSC-NASA partnership at NASA Ames Research Center at Moffett Field. "In the campus labs we do mostly basic science. The SERF lab provides a good setting for applied research and collaborations with industry and NASA partners," Carter said.

####

For more information, please click here

Contacts:
Tim Stephens
(831) 459-2495

Copyright © University of California, Santa Cruz

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

'Nano-hashtags' could provide definite proof of Majorana particles: Eindhoven network of nanowires gives particles the space to exchange places August 23rd, 2017

DNA sensor system developed for specific and sensitive measurement of cancer-relevant enzyme activity August 23rd, 2017

Lego proteins revealed: Self-assembling protein complexes based on a single mutation could provide scaffolding for nanostructures August 23rd, 2017

Heating quantum matter: A novel view on topology: Physicists demonstrate how heating up a quantum system can be used as a universal probe for exotic states of matter August 22nd, 2017

Thin films

Rice University chemists make laser-induced graphene from wood July 31st, 2017

Graduate Students from Across the Country Attend Hands-on NanoCamp: Prominent scientists Warren Oliver, Ph.D., and George Pharr, Ph.D., presented a weeklong NanoCamp for hand-picked graduate students across the United States July 26th, 2017

Studying Argon Gas Trapped in Two-Dimensional Array of Tiny "Cages": Understanding how individual atoms enter and exit the nanoporous frameworks could help scientists design new materials for gas separation and nuclear waste remediation July 17th, 2017

Thinking thin brings new layering and thermal abilities to the semiconductor industry: In a breakthrough for the semiconductor industry, researchers demonstrate a new layer transfer technique called "controlled spalling" that creates many thin layers from a single gallium nitride July 11th, 2017

Govt.-Legislation/Regulation/Funding/Policy

'Nano-hashtags' could provide definite proof of Majorana particles: Eindhoven network of nanowires gives particles the space to exchange places August 23rd, 2017

Nagoya physicists resolve long-standing mystery of structure-less transition: Nagoya University-led team of physicists use a synchrotron radiation X-ray source to probe a so-called 'structure-less' transition and develop a new understanding of molecular conductors August 21st, 2017

Researchers printed graphene-like materials with inkjet August 17th, 2017

Freeze-dried foam soaks up carbon dioxide: Rice University scientists lead effort to make novel 3-D material August 16th, 2017

Academic/Education

Two Scientists Receive Grants to Develop New Materials: Chad Mirkin and Monica Olvera de la Cruz recognized by Sherman Fairchild Foundation August 16th, 2017

Moving at the Speed of Light: University of Arizona selected for high-impact, industrial demonstration of new integrated photonic cryogenic datalink for focal plane arrays: Program is major milestone for AIM Photonics August 10th, 2017

Graduate Students from Across the Country Attend Hands-on NanoCamp: Prominent scientists Warren Oliver, Ph.D., and George Pharr, Ph.D., presented a weeklong NanoCamp for hand-picked graduate students across the United States July 26th, 2017

The Physics Department of Imperial College, London, uses the Quorum Q150T to deposit metals and ITO to make plasmonic sensors and electric contact pads July 13th, 2017

Announcements

'Nano-hashtags' could provide definite proof of Majorana particles: Eindhoven network of nanowires gives particles the space to exchange places August 23rd, 2017

DNA sensor system developed for specific and sensitive measurement of cancer-relevant enzyme activity August 23rd, 2017

Lego proteins revealed: Self-assembling protein complexes based on a single mutation could provide scaffolding for nanostructures August 23rd, 2017

Heating quantum matter: A novel view on topology: Physicists demonstrate how heating up a quantum system can be used as a universal probe for exotic states of matter August 22nd, 2017

Energy

The power of perovskite: OIST researchers improve perovskite-based technology in the entire energy cycle, from solar cells harnessing power to LED diodes to light the screens of future electronic devices and other lighting applications August 18th, 2017

Freeze-dried foam soaks up carbon dioxide: Rice University scientists lead effort to make novel 3-D material August 16th, 2017

Two Scientists Receive Grants to Develop New Materials: Chad Mirkin and Monica Olvera de la Cruz recognized by Sherman Fairchild Foundation August 16th, 2017

Fewer defects from a 2-D approach August 15th, 2017

Solar/Photovoltaic

The power of perovskite: OIST researchers improve perovskite-based technology in the entire energy cycle, from solar cells harnessing power to LED diodes to light the screens of future electronic devices and other lighting applications August 18th, 2017

Fewer defects from a 2-D approach August 15th, 2017

Controlled manipulation: Scientists at FAU are investigating the properties of hybrid systems consisting of carbon nanostructures and a dye August 8th, 2017

Simultaneous Design and Nanomanufacturing Speeds Up Fabrication: Method enhances broadband light absorption in solar cells August 5th, 2017

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project