Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New theory may lead to more efficient solar cells

29.01.2014
UH collaboration with Universite de Montreal published in Nature Communications

A new theoretical model developed by professors at the University of Houston (UH) and Université de Montréal may hold the key to methods for developing better materials for solar cells.

Eric Bittner, a John and Rebecca Moores Professor of Chemistry and Physics in UH's College of Natural Sciences and Mathematics, and Carlos Silva, an associate professor at the Université de Montréal and Canada Research Chair in Organic Semiconductor Materials, say the model could lead to new solar cell materials made from improved blends of semiconducting polymers and fullerenes.

The researchers describe their findings in a paper titled "Noise-Induced Quantum Coherence Drives Photo-Carrier Generation Dynamics at Polymeric Semiconductor Heterojunctions," appearing Jan. 29 in Nature Communications, a multidisciplinary journal dedicated to publishing research in the biological, physical and chemical sciences.

"Scientists don't fully understand what is going on inside the materials that make up solar cells. We were trying to get at the fundamental photochemistry or photophysics that describes how these cells work," Bittner said.

Solar cells are made out of organic semiconductors – typically blends of materials. However, solar cells made of these materials have about 3 percent efficiency. Bittner added that the newer materials, the fullerene/polymer blends, only reach about 10 percent efficiency.

"There is a theoretical limit for the efficiency of the ideal solar cell – the Shockley-Queisser limit. The theory we published describes how we might be able to get above this theoretical limit by taking advantage of quantum mechanical effects," Bittner said. "By understanding these effects and making use of them in the design of a solar cell, we believe you can improve efficiency."

Silva added, "In polymeric semiconductors, where plastics form the active layer of solar cells, the electronic structure of the material is intimately correlated with the vibrational motion within the polymer chain. Quantum-mechanical effects due to such vibrational-electron coupling give rise to a plethora of interesting physical processes that can be controlled to optimize solar cell efficiencies by designing materials that best exploit them."

The idea for the model was born while Bittner was a Fulbright Canada Scholar and visiting professor at the Université de Montréal collaborating with Silva, an expert in the field of ultrafast laser spectroscopy and organic semiconductors.

Bittner says the benefit of their model is that it provides insight into what is happening in solar cell systems.

"Our theoretical model accomplishes things that you can't get from a molecular model," he said. "It is mostly a mathematical model that allows us to look at a much larger system with thousands of molecules. You can't do ordinary quantum chemistry calculations on a system of that size."

The calculations have prompted a series of new experiments by Silva's group to probe the outcomes predicted by their model.

Bittner and Silva's next steps involve collaborations with researchers who are experts in making the polymers and fabricating solar cells.

The work at UH was funded by the Robert Welch Foundation and the National Science Foundation. The work in Canada was supported by the National Sciences and Engineering Research Council of Canada.

Media contact for Université de Montréal: Julie Gazaille, medias@umontreal.ca or (1) 514-343-6796

Editor's note: Story courtesy of Kathy Major, College of Natural Sciences and Mathematics

About the University of Houston

The University of Houston is a Carnegie-designated Tier One public research university recognized by The Princeton Review as one of the nation's best colleges for undergraduate education. UH serves the globally competitive Houston and Gulf Coast Region by providing world-class faculty, experiential learning and strategic industry partnerships. Located in the nation's fourth-largest city, UH serves more than 39,500 students in the most ethnically and culturally diverse region in the country. For more information about UH, visit the university's newsroom at http://www.uh.edu/news-events/.

About the College of Natural Sciences and Mathematics

The UH College of Natural Sciences and Mathematics, with 193 ranked faculty and nearly 6,000 students, offers bachelor's, master's and doctoral degrees in the natural sciences, computational sciences and mathematics. Faculty members in the departments of biology and biochemistry, chemistry, computer science, earth and atmospheric sciences, mathematics and physics conduct internationally recognized research in collaboration with industry, Texas Medical Center institutions, NASA and others worldwide.

About Université de Montréal

Université de Montréal enjoys an enviable position as a leading research institution both in North America and the French-speaking world. The university's role as a hub between these spheres enables it to develop unique and dynamic research networks that are driven by world-renowned scientists, drawing collaboration with the globe's most innovative organizations. At a local level, the University is committed to building on the Montreal region's unique strengths in science and technology, encompassing fields such as aerospace engineering, nanoscale chemistry and software design, and has therefore promoted strategic relationships with public and private organizations. For more information about UM, visit the university's newsroom at http://www.umontreal.ca/english/index.html .

To receive UH science news via email, sign up for UH-SciNews at http://www.uh.edu/news-events/mailing-lists/sciencelistserv/index.php.

For additional news alerts about UH, follow us on Facebook at http://www.facebook.com/UHNewsEvents and Twitter at http://twitter.com/UH_News.

Lisa Merkl | EurekAlert!
Further information:
http://www.uh.edu

More articles from Power and Electrical Engineering:

nachricht Another Milestone in Hybrid Artificial Photosynthesis
31.08.2015 | Lawrence Berkeley National Laboratory

nachricht New high energy density automotive battery system from Fraunhofer IISB and international partners
25.08.2015 | Fraunhofer-Gesellschaft

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Increasingly severe disturbances weaken world's temperate forests

Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening to transform some of the world's temperate forests, a new study published in Science has found. Without informed management, some forests could convert to shrublands or grasslands within the coming decades.

"While we have been trying to manage for resilience of 20th century conditions, we realize now that we must prepare for transformations and attempt to ease...

Im Focus: OU astrophysicist and collaborators find supermassive black holes in quasar nearest Earth

A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.

The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...

Im Focus: What would a tsunami in the Mediterranean look like?

A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).

Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...

Im Focus: Self-healing landscape: landslides after earthquake

In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.

These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...

Im Focus: FIC Proteins Send Bacteria Into Hibernation

Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.

For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking conference in Heidelberg for outstanding mathematicians and computer scientists

20.08.2015 | Event News

Scientists meet in Münster for the world’s largest Chitin und Chitosan Conference

20.08.2015 | Event News

Large agribusiness management strategies

19.08.2015 | Event News

 
Latest News

Production research by Fraunhofer IAO honored with three awards at the ICPR 2015

31.08.2015 | Awards Funding

Single-Crystal Phosphors Suitable for Ultra-Bright, High-Power White Light Sources

31.08.2015 | Materials Sciences

Manchester Team Reveal New, Stable 2D Materials

31.08.2015 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>