Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > NREL Nano-Technology Solar Cell Achieves 18.2% Efficiency: Breakthrough should eliminate need for anti-reflection layer, cutting costs

Abstract:
Scientists at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) have produced solar cells using nanotechnology techniques at an efficiency - 18.2% -- that is competitive. The breakthrough should be a major step toward helping lower the cost of solar energy.

NREL Nano-Technology Solar Cell Achieves 18.2% Efficiency: Breakthrough should eliminate need for anti-reflection layer, cutting costs

Golden, CO | Posted on October 12th, 2012

NREL tailored a nanostructured surface while ensuring that the light-generated electricity can still be collected efficiently from the solar cell. The researchers made nano-islands of silver on a silicon wafer and immersed it briefly in liquids to make billions of nano-sized holes in each square-inch of the silicon wafer surface. The holes and silicon walls are smaller than the light wavelengths hitting them, so the light doesn't recognize any sudden change in density at the surface and, thus, don't reflect back into the atmosphere as wasted energy. The researchers controlled the nanoshapes and the chemical composition of the surface to reach record solar cell efficiencies for this 'black silicon' material.

The paper, "An 18.2%-efficient black-silicon solar cell achieved through control of carrier recombination in nanostructures" by NREL's Jihun Oh, Hao-Chih Yuan, and Howard Branz, currently appears on Nature Nanotechnology's website.

Typically, solar cell manufacturers must add an extra anti-reflection layer, or two, to their cells, which boosts costs significantly.

NREL previously had demonstrated that their nanostructures reflected less light than the best anti-reflection layers of a solar cell. But until now, they hadn't been able to achieve overall efficiency with their black silicon cells that could approach the best marks for other silicon cells.

Oh, Yuan, and Branz, first had to determine why the increased surface area of the nanostructures dramatically reduced the collection of electricity and hurt the voltage and current of the cells.

Their experiments demonstrated that the high-surface area, and especially a process called Auger recombination, limit the collection of photons on most nanostructured solar cells. They concluded that this Auger recombination is caused when too many of the dopant impurities put in to make the cell work come through the nanostructured surface.

This scientific understanding enabled them to suppress Auger recombination with lighter and shallower doping. Combining this lighter doping with slightly smoother nanoshapes, they can build an 18.2%-efficient solar cell that is black but responds nearly ideally to almost the entire solar spectrum.

The Energy Department funded the research grant through the American Recovery and Reinvestment Act.

Branz, the grant's principal investigator, said, "This work can have a big impact on both conventional and emerging solar cell based on nanowires and nanospheres. For the first time it shows that really great solar cells can be made from nanostructured semiconductors."

Branz added, "The next challenges are to translate these results to common industrial practice and then get the efficiency over 20%. After that, I hope to see these kinds of nanostructuring techniques used on far thinner cells to use less semiconductor material."

"Now we have a clear study that shows how optimizing the surface area and the doping together can give better efficiency," Yuan said. "The surface area and the doping concentration near the surface affect nano-structured solar-cell performance."

First author, Oh, an NREL Postdoctoral Fellow said the NREL study "clearly shows that the right combination of a carefully nano-structured surface and good processing can reduce the cost while cutting unwanted reflection of sunlight."

####

About National Renewable Energy Laboratory (NREL)
NREL is the U.S. Department of Energy's primary national laboratory for renewable energy and energy efficiency research and development. NREL is operated for DOE by the Alliance for Sustainable Energy, LLC.

For more information, please click here

Contacts:
William Scanlon
303-275-4051

Copyright © National Renewable Energy Laboratory (NREL)

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 Links

Download paper - "An 18.2%-efficient black-silicon solar cell achieved through control of carrier recombination in nanostructures.":

Related News Press

News and information

Quantum networks: Back and forth are not equal distances! July 28th, 2015

Smart hydrogel coating creates 'stick-slip' control of capillary action July 27th, 2015

Industrial Nanotech, Inc. Provides Update on PCAOB Audited Financials July 27th, 2015

Global Corrosion Resistant Nano Coatings Market To 2015: Acute Market Reports July 27th, 2015

Laboratories

Superfast fluorescence sets new speed record: Plasmonic device has speed and efficiency to serve optical computers July 27th, 2015

Ultra-thin hollow nanocages could reduce platinum use in fuel cell electrodes July 24th, 2015

ORNL researchers make scalable arrays of 'building blocks' for ultrathin electronics July 22nd, 2015

Simulations lead to design of near-frictionless material July 21st, 2015

Govt.-Legislation/Regulation/Funding/Policy

Smart hydrogel coating creates 'stick-slip' control of capillary action July 27th, 2015

Researchers predict material with record-setting melting point July 27th, 2015

Reshaping the solar spectrum to turn light to electricity: UC Riverside researchers find a way to use the infrared region of the sun's spectrum to make solar cells more efficient July 27th, 2015

Superfast fluorescence sets new speed record: Plasmonic device has speed and efficiency to serve optical computers July 27th, 2015

Discoveries

Quantum networks: Back and forth are not equal distances! July 28th, 2015

Smaller, faster, cheaper: A new type of modulator for the future of data transmission July 27th, 2015

Researchers predict material with record-setting melting point July 27th, 2015

Reshaping the solar spectrum to turn light to electricity: UC Riverside researchers find a way to use the infrared region of the sun's spectrum to make solar cells more efficient July 27th, 2015

Announcements

Quantum networks: Back and forth are not equal distances! July 28th, 2015

Reshaping the solar spectrum to turn light to electricity: UC Riverside researchers find a way to use the infrared region of the sun's spectrum to make solar cells more efficient July 27th, 2015

Industrial Nanotech, Inc. Provides Update on PCAOB Audited Financials July 27th, 2015

Global Corrosion Resistant Nano Coatings Market To 2015: Acute Market Reports July 27th, 2015

Energy

Smaller, faster, cheaper: A new type of modulator for the future of data transmission July 27th, 2015

Reshaping the solar spectrum to turn light to electricity: UC Riverside researchers find a way to use the infrared region of the sun's spectrum to make solar cells more efficient July 27th, 2015

Industrial Nanotech, Inc. Provides Update on PCAOB Audited Financials July 27th, 2015

Ultra-thin hollow nanocages could reduce platinum use in fuel cell electrodes July 24th, 2015

Solar/Photovoltaic

Reshaping the solar spectrum to turn light to electricity: UC Riverside researchers find a way to use the infrared region of the sun's spectrum to make solar cells more efficient July 27th, 2015

Rice University finding could lead to cheap, efficient metal-based solar cells: Plasmonics study suggests how to maximize production of 'hot electrons' July 22nd, 2015

Perovskite solar technology shows quick energy returns: New technology beats current solar panel technology in life-cycle energy assessment July 20th, 2015

Nanowires give 'solar fuel cell' efficiency a tenfold boost: Eindhoven researchers make important step towards a solar cell that generates hydrogen July 17th, 2015

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