Navigation Links
Stanford scientists build the first all-carbon solar cell
Date:10/31/2012

Stanford University scientists have built the first solar cell made entirely of carbon, a promising alternative to the expensive materials used in photovoltaic devices today.

The results are published in the Oct. 31 online edition of the journal ACS Nano.

"Carbon has the potential to deliver high performance at a low cost," said study senior author Zhenan Bao, a professor of chemical engineering at Stanford. "To the best of our knowledge, this is the first demonstration of a working solar cell that has all of the components made of carbon. This study builds on previous work done in our lab."

Unlike rigid silicon solar panels that adorn many rooftops, Stanford's thin film prototype is made of carbon materials that can be coated from solution. "Perhaps in the future we can look at alternative markets where flexible carbon solar cells are coated on the surface of buildings, on windows or on cars to generate electricity," Bao said.

The coating technique also has the potential to reduce manufacturing costs, said Stanford graduate student Michael Vosgueritchian, co-lead author of the study with postdoctoral researcher Marc Ramuz.

"Processing silicon-based solar cells requires a lot of steps," Vosgueritchian explained. "But our entire device can be built using simple coating methods that don't require expensive tools and machines."

Carbon nanomaterials

The Bao group's experimental solar cell consists of a photoactive layer, which absorbs sunlight, sandwiched between two electrodes. In a typical thin film solar cell, the electrodes are made of conductive metals and indium tin oxide (ITO). "Materials like indium are scarce and becoming more expensive as the demand for solar cells, touchscreen panels and other electronic devices grows," Bao said. "Carbon, on the other hand, is low cost and Earth-abundant."

For the study, Bao and her colleagues replaced the silver and ITO used in conventional electrodes with graphene sheets of carbon that are one atom thick and single-walled carbon nanotubes that are 10,000 times narrower than a human hair. "Carbon nanotubes have extraordinary electrical conductivity and light-absorption properties," Bao said.

For the active layer, the scientists used material made of carbon nanotubes and "buckyballs" soccer ball-shaped carbon molecules just one nanometer in diameter. The research team recently filed a patent for the entire device.

"Every component in our solar cell, from top to bottom, is made of carbon materials," Vosgueritchian said. "Other groups have reported making all-carbon solar cells, but they were referring to just the active layer in the middle, not the electrodes."

One drawback of the all-carbon prototype is that it primarily absorbs near-infrared wavelengths of light, contributing to a laboratory efficiency of less than 1 percent much lower than commercially available solar cells. "We clearly have a long way to go on efficiency," Bao said. "But with better materials and better processing techniques, we expect that the efficiency will go up quite dramatically."

Improving efficiency

The Stanford team is looking at a variety of ways to improve efficiency. "Roughness can short-circuit the device and make it hard to collect the current," Bao said. "We have to figure out how to make each layer very smooth by stacking the nanomaterials really well."

The researchers are also experimenting with carbon nanomaterials that can absorb more light in a broader range of wavelengths, including the visible spectrum.

"Materials made of carbon are very robust," Bao said. "They remain stable in air temperatures of nearly 1,100 degrees Fahrenheit."

The ability of carbon solar cells to out-perform conventional devices under extreme conditions could overcome the need for greater efficiency, according to Vosgueritchian. "We believe that all-carbon solar cells could be used in extreme environments, such as at high temperatures or at high physical stress," he said. "But obviously we want the highest efficiency possible and are working on ways to improve our device."

"Photovoltaics will definitely be a very important source of power that we will tap into in the future," Bao said. "We have a lot of available sunlight. We've got to figure out some way to use this natural resource that is given to us."


'/>"/>

Contact: Mark Shwartz
mshwartz@stanford.edu
650-723-9296
Stanford University
Source:Eurekalert  

Related biology news :

1. Stanford scientists develop gene therapy approach to grow blood vessels in ischemic limbs
2. Keck award enables Carnegie Mellon and Stanford to dramatically expand crowdsourced RNA design
3. Climate change may create price volatility in the corn market, say Stanford and Purdue researchers
4. Stanford and MIT scientists win Perl-UNC Neuroscience prize
5. Americas clean energy policies need a reality check, say Stanford researchers
6. Support for climate change action drops, Stanford poll finds
7. Stanford scientists document fragile land-sea ecological chain
8. Stanford researchers help predict the oceans of the future with a mini-lab
9. Stanford marine biologist Barbara Block wins Rolex Award for Enterprise
10. Stanford scientists find molecule to starve lung cancer and improve ventilator recovery
11. Stanford researchers calculate global health impacts of the Fukushima nuclear disaster
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Stanford scientists build the first all-carbon solar cell
(Date:4/19/2017)... New York , April 19, 2017 ... competitive, as its vendor landscape is marked by the ... the market is however held by five major players ... Safran. Together these companies accounted for nearly 61% of ... of the leading companies in the global military biometrics ...
(Date:4/13/2017)... India , April 13, 2017 According to ... Proofing, Identity Authentication, Identity Analytics, Identity Administration, and Authorization), Service, Authentication Type, ... MarketsandMarkets™, the IAM Market is expected to grow from USD 14.30 Billion ... Growth Rate (CAGR) of 17.3%. ... MarketsandMarkets ...
(Date:4/11/2017)... , April 11, 2017 NXT-ID, ... security technology company, announces the appointment of independent Directors Mr. ... to its Board of Directors, furthering the company,s corporate ... ... NXT-ID, we look forward to their guidance and benefiting from ...
Breaking Biology News(10 mins):
(Date:8/16/2017)... ... August 16, 2017 , ... Tunnell Consulting announced today that four ... ISPE Annual Meeting and Expo , to be held October 29 through November 1 ... “Driving innovation to advance patient therapies.” , The ISPE Annual Meeting and Expo will ...
(Date:8/16/2017)... PA (PRWEB) , ... August 16, 2017 , ... While ... they are much more closely connected than one might think. A Mesh Is ... will open at the University City Science Center’s Esther Klein Gallery (EKG) on August ...
(Date:8/16/2017)... -- This year,s edition of the Inc. 5000 features a now-familiar name: BioPoint ... made the list for the third year in a row. Now in ... based on a set of quantitative metrics. In addition, BioPoint was also ... the Bay State . ... Inc. 5000 ...
(Date:8/15/2017)... ... August 15, 2017 , ... Kapstone Medical is proud ... successes helping medical technology companies and inventors develop and safeguard their latest innovations. ... engineering firm with a portfolio of clients in the United States and around the ...
Breaking Biology Technology: