Featured Research

from universities, journals, and other organizations

Revolutionizing solar energy: Quantum waves found at the heart of organic solar cells

Date:
December 12, 2013
Source:
University of Cambridge
Summary:
Researchers have been able to tune ‘coherence’ in organic nanostructures due to the surprise discovery of wavelike electrons in organic materials, revealing the key to generating “long-lived charges” in organic solar cells - material that could revolutionize solar energy.

This is the experimental setup used to generate femtosecond laser pulses which serve as an ultrafast "flash" for the camera so that very rapid phenomenon can be filmed.
Credit: Simon Gelinas

Researchers have been able to tune ‘coherence’ in organic nanostructures due to the surprise discovery of wavelike electrons in organic materials, revealing the key to generating “long-lived charges” in organic solar cells - material that could revolutionise solar energy.

By using an ultrafast camera, scientists say they have observed the very first instants following the absorption of light into artificial yet organic nanostructures and found that charges not only formed rapidly but also separated very quickly over long distances - phenomena that occur due to the wavelike nature of electrons which are governed by fundamental laws of quantum mechanics.

This result surprised scientists as such phenomena were believed to be limited to “perfect” - and expensive - inorganic structures; rather than the soft, flexible organic material believed by many to be the key to cheap, ‘roll-to-roll’ solar cells that could be printed at room temperatures - a very different world from the traditional but costly processing of current silicon technologies. 

The study, published today in the journal Science, sheds new light on the mystery mechanism that allows positive and negative charges to be separated efficiently - a critical question that continues to puzzle scientists - and takes researchers a step closer to effectively mimicking the highly efficient ability to harvest sunlight and convert into energy, namely photosynthesis, which the natural world evolved over the course of millennia.

“This is a very surprising result. Such quantum phenomena are usually confined to perfect crystals of inorganic semiconductors, and one does not expect to see such effects in organic molecules - which are very disordered and tend to resemble a plate of cooked spaghetti rather than a crystal,” said Dr Simon Gιlinas, from Cambridge’s Cavendish Laboratory, who led the research with colleagues from Cambridge as well as the University of California in Santa Barbara.

During the first few femtoseconds (one millionth of one billionth of a second) each charge spreads itself over multiple molecules rather than being localised to a single one. This phenomenon, known as spatial coherence, allows a charge to travel very quickly over several nanometres and escape from its oppositely charged partner - an initial step which seems to be the key to generating long-lived charges, say the researchers. This can then be used to generate electricity or for chemical reactions.

By carefully engineering the way molecules pack together, the team found that it was possible to tune the spatial coherence and to amplify - or reduce - this long-range separation. “Perhaps most importantly the results suggest that because the process is so fast it is also energy efficient, which could result in more energy out of the solar cell,” said Dr Akshay Rao, a co-author on the study from the Cavendish Laboratory.

Dr Alex Chin, who led the theoretical part of the project, added that, if you look beyond the implications of the study for organic solar cells, this is a clear demonstration of “how fundamental quantum-mechanical processes, such as coherence, play a crucial role in disordered organic and biological systems and can be harnessed in new quantum technologies”.


Story Source:

The above story is based on materials provided by University of Cambridge. The original story is licensed under a Creative Commons Licence. Note: Materials may be edited for content and length.


Journal Reference:

  1. Simon Gιlinas, Akshay Rao, Abhishek Kumar, Samuel L. Smith, Alex W. Chin, Jenny Clark, Tom S. van der Poll, Guillermo C. Bazan, and Richard H. Friend. Ultrafast Long-Range Charge Separation in Organic Semiconductor Photovoltaic Diodes. , 12 December 2013 DOI: 10.1126/science.1246249

Cite This Page:

University of Cambridge. "Revolutionizing solar energy: Quantum waves found at the heart of organic solar cells." ScienceDaily. ScienceDaily, 12 December 2013. <www.sciencedaily.com/releases/2013/12/131212142059.htm>.
University of Cambridge. (2013, December 12). Revolutionizing solar energy: Quantum waves found at the heart of organic solar cells. ScienceDaily. Retrieved August 29, 2014 from www.sciencedaily.com/releases/2013/12/131212142059.htm
University of Cambridge. "Revolutionizing solar energy: Quantum waves found at the heart of organic solar cells." ScienceDaily. www.sciencedaily.com/releases/2013/12/131212142059.htm (accessed August 29, 2014).

Share This




More Earth & Climate News

Friday, August 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Killer Amoeba Found in Louisiana Water System

Killer Amoeba Found in Louisiana Water System

AP (Aug. 28, 2014) — State health officials say testing has confirmed the presence of a killer amoeba in a water system serving three St. John the Baptist Parish towns. (Aug. 28) Video provided by AP
Powered by NewsLook.com
Scientists Have Figured Out Why Rocks Move In Death Valley

Scientists Have Figured Out Why Rocks Move In Death Valley

Newsy (Aug. 28, 2014) — The mystery of the moving rocks in Death Valley, California, has finally been solved. Scientists are pointing to a combo of water, ice and wind. Video provided by Newsy
Powered by NewsLook.com
Big Waves, Minor Flooding from Hurricane

Big Waves, Minor Flooding from Hurricane

AP (Aug. 27, 2014) — Thundering surf spawned by Hurricane Marie pounded the Southern California coast Wednesday, causing minor flooding in a low-lying beach town. High surf warnings were posted for Los Angeles County south through Orange County. (Aug. 27) Video provided by AP
Powered by NewsLook.com
Calif. Quake Underscores Need for Early Warning

Calif. Quake Underscores Need for Early Warning

AP (Aug. 26, 2014) — Researchers at UC Berkeley are testing a prototype of an earthquake early warning system that California is pursuing years after places like Mexico and Japan already have them up and running. (August 26) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins