Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > NIST Scientists Study How to Stack the Deck for Organic Solar Power

In this cross-section of an organic photovoltaic cell, light passes through the upper layers (from top down, glass, indium tin dioxide, and thermoplastic) and generates a photocurrent in the polymer-fullerene layer. Channels formed by polymers (tan) and fullerenes (dark blue) allow electric current to flow into the electrode at bottom. NIST research has revealed new information about how the channels form, potentially improving cell performance.

Credit: NIST
In this cross-section of an organic photovoltaic cell, light passes through the upper layers (from top down, glass, indium tin dioxide, and thermoplastic) and generates a photocurrent in the polymer-fullerene layer. Channels formed by polymers (tan) and fullerenes (dark blue) allow electric current to flow into the electrode at bottom. NIST research has revealed new information about how the channels form, potentially improving cell performance. Credit: NIST

Abstract:
A new class of economically viable solar power cells—cheap, flexible and easy to make—has come a step closer to reality as a result of recent work* at the National Institute of Standards and Technology (NIST), where scientists have deepened their understanding of the complex organic films at the heart of the devices.

NIST Scientists Study How to Stack the Deck for Organic Solar Power

Gaithersburg, MD | Posted on August 5th, 2009

Organic photovoltaics, which rely on organic molecules to capture sunlight and convert it into electricity, are a hot research area because in principle they have significant advantages over traditional rigid silicon cells. Organic photovoltaics start out as a kind of ink that can be applied to flexible surfaces to create solar cell modules that can be spread over large areas as easily as unrolling a carpet. They'd be much cheaper to make and easier to adapt to a wide variety of power applications, but their market share will be limited until the technology improves. Even the best organic photovoltaics convert less than 6 percent of light into electricity and last only a few thousand hours. "The industry believes that if these cells can exceed 10 percent efficiency and 10,000 hours of life, technology adoption will really accelerate," says NIST's David Germack. "But to improve them, there is critical need to identify what's happening in the material, and at this point, we're only at the beginning."

The NIST team has advanced that understanding with their latest effort, which provides a powerful new measurement strategy for organic photovoltaics that reveals ways to control how they form. In the most common class of organic photovoltaics, the "ink" is a blend of a polymer that absorbs sunlight, enabling it to give up its electrons, and ball-shaped carbon molecules called fullerenes that collect electrons. When the ink is applied to a surface, the blend hardens into a film that contains a haphazard network of polymers intermixed with fullerene channels. In conventional devices, the polymer network should ideally all reach the bottom of the film while the fullerene channels should ideally all reach the top, so that electricity can flow in the correct direction out of the device. However, if barriers of fullerenes form between the polymers and the bottom edge of the film, the cell's efficiency will be reduced.

By applying X-ray absorption measurements to the film interfaces, the team discovered that by changing the nature of the electrode surface, it will repulse fullerenes (like oil repulses water) while attracting the polymer. The electrical properties of the interface also change dramatically. The resultant structure gives the light-generated photocurrent more opportunities to reach the proper electrodes and reduces the accumulation of fullerenes at the film bottom, both of which could improve the photovoltaic's efficiency or lifetime.

"We've identified some key parameters needed to optimize what happens at both edges of the film, which means the industry will have a strategy to optimize the cell's overall performance," Germack says. "Right now, we're building on what we've learned about the edges to identify what happens throughout the film. This knowledge is really important to help industry figure out how organic cells perform and age so that their life spans will be extended."

* D.S. Germack, C.K. Chan, B.H. Hamadani, L.J. Richter, D.A. Fischer, D.J. Gundlach and D.M. DeLongchamp. Substrate-dependent interface composition and charge transport in films for organic photovoltaics. Applied Physics Letters, 94, 233303 (2009), DOI: 10.1063/1.3149706.

####

About National Institute of Standards and Technology
From automated teller machines and atomic clocks to mammograms and semiconductors, innumerable products and services rely in some way on technology, measurement, and standards provided by the National Institute of Standards and Technology.

Founded in 1901, NIST is a non-regulatory federal agency within the U.S. Department of Commerce. NIST's mission is to promote U.S. innovation and industrial competitiveness by advancing measurement science, standards, and technology in ways that enhance economic security and improve our quality of life.

For more information, please click here

Contacts:
Media Contact
Chad Boutin

(301) 975-4261

Copyright © National Institute of Standards and Technology

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

Vegetable oil ingredient key to destroying gastric disease bacteria: In mice, therapeutic nanoparticles dampen H. pylori bacteria and inflammation that lead to ulcers and gastric cancer November 25th, 2014

Research yields material made of single-atom layers that snap together like Legos November 25th, 2014

Blu-ray disc can be used to improve solar cell performance: Data storage pattern transferred to solar cell increases light absorption November 25th, 2014

A*STAR SIMTech wins international award for breaking new ground in actuators: SIMTech invention can be used in an array of industries, and is critical for next generation ultra-precision systems November 24th, 2014

Thin films

New way to move atomically thin semiconductors for use in flexible devices November 13th, 2014

Graphene Frontiers Partners with Madico to Accelerate Material Production: Deal to ignite and fulfill demand for industrial scale graphene film that supports energy, consumer electronics, membranes/filtration, solar and other applications November 12th, 2014

New materials for more powerful solar cells: Major breakthrough in solar energy November 11th, 2014

Drexel Engineers Improve Strength, Flexibility of Atom-Thick Films November 11th, 2014

Possible Futures

A novel method for identifying the body’s ‘noisiest’ networks November 19th, 2014

Researchers discern the shapes of high-order Brownian motions November 17th, 2014

VDMA Electronics Production Equipment: Growth track for 2014 and 2015 confirmed: Business climate survey shows robust industry sector November 14th, 2014

Open Materials Development Will Be Key for HP's Success in 3D Printing: HP can make a big splash in 3D printing, but it needs to shore up technology claims and avoid the temptation of the razor/razor blade business model in order to flourish November 11th, 2014

Announcements

Vegetable oil ingredient key to destroying gastric disease bacteria: In mice, therapeutic nanoparticles dampen H. pylori bacteria and inflammation that lead to ulcers and gastric cancer November 25th, 2014

Research yields material made of single-atom layers that snap together like Legos November 25th, 2014

Blu-ray disc can be used to improve solar cell performance: Data storage pattern transferred to solar cell increases light absorption November 25th, 2014

Cooling with the coldest matter in the world November 24th, 2014

Energy

Research yields material made of single-atom layers that snap together like Legos November 25th, 2014

Blu-ray disc can be used to improve solar cell performance: Data storage pattern transferred to solar cell increases light absorption November 25th, 2014

UO-industry collaboration points to improved nanomaterials: University of Oregon microscope puts spotlight on the surface structure of quantum dots for designing new solar devices November 20th, 2014

Eight19 secures £1m funding: Investment to develop production technology, and expand commercial activities for organic photovoltaics November 19th, 2014

Solar/Photovoltaic

Research yields material made of single-atom layers that snap together like Legos November 25th, 2014

Blu-ray disc can be used to improve solar cell performance: Data storage pattern transferred to solar cell increases light absorption November 25th, 2014

UO-industry collaboration points to improved nanomaterials: University of Oregon microscope puts spotlight on the surface structure of quantum dots for designing new solar devices November 20th, 2014

Eight19 secures £1m funding: Investment to develop production technology, and expand commercial activities for organic photovoltaics November 19th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE