Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Revolutionary solar cells double as lasers

This is an image of the laboratory in which the research was conducted.

Credit: Winton Programme for the Physics of Sustainability
This is an image of the laboratory in which the research was conducted.

Credit: Winton Programme for the Physics of Sustainability

Abstract:
Commercial silicon-based solar cells - such as those seen on the roofs of houses across the country - operate at about 20% efficiency for converting the Sun's rays into electrical energy. It's taken over 20 years to achieve that rate of efficiency.

Revolutionary solar cells double as lasers

Cambridge, UK | Posted on March 28th, 2014

A relatively new type of solar cell based on a perovskite material - named for scientist Lev Perovski, who first discovered materials with this structure in the Ural Mountains in the 19th century - was recently pioneered by an Oxford research team led by Professor Henry Snaith.

Perovskite solar cells, the source of huge excitement in the research community, already lie just a fraction behind commercial silicon, having reached a remarkable 17% efficiency after a mere two years of research - transforming prospects for cheap large-area solar energy generation.

Now, researchers from Professor Sir Richard Friend's group at Cambridge's Cavendish Laboratory - working with Snaith's Oxford group - have demonstrated that perovskite cells excel not just at absorbing light but also at emitting it. The new findings, recently published online in the Journal of Physical Chemistry Letters [doi 10.1021/jz500528], show that these 'wonder cells' can also produce cheap lasers.

By sandwiching a thin layer of the lead halide perovskite between two mirrors, the team produced an optically driven laser which proves these cells "show very efficient luminescence" - with up to 70% of absorbed light re-emitted.

The researchers point to the fundamental relationship, first established by Shockley and Queisser in 1961, between the generation of electrical charges following light absorption and the process of 'recombination' of these charges to emit light.

Essentially, if a material is good at converting light to electricity, then it will be good at converting electricity to light. The lasing properties in these materials raise expectations for even higher solar cell efficiencies, say the Oxbridge team, which - given that perovskite cells are about to overtake commercial cells in terms of efficiency after just two years of development - is a thrilling prospect.

"This first demonstration of lasing in these cheap solution-processed semiconductors opens up a range of new applications," said lead author Dr Felix Deschler of the Cavendish Laboratory. "Our findings demonstrate potential uses for this material in telecommunications and for light emitting devices."

Most commercial solar cell materials need expensive processing to achieve a very low level of impurities before they show good luminescence and performance. Surprisingly these new materials work well even when very simply prepared as thin films using cheap scalable solution processing.

The researchers found that upon light absorption in the perovskite two charges (electron and hole) are formed very quickly - within 1 picosecond - but then take anywhere up to a few microseconds to recombine. This is long enough for chemical defects to have ceased the light emission in most other semiconductors, such as silicon or gallium arsenide. "These long carrier lifetimes together with exceptionally high luminescence are unprecedented in such simply prepared inorganic semiconductors," said Dr Sam Stranks, co-author from the Oxford University team.

"We were surprised to find such high luminescence efficiency in such easily prepared materials. This has great implications for improvements in solar cell efficiency," said Michael Price, co-author from the group in Cambridge.

Added Snaith: "This luminescent behaviour is an excellent test for solar cell performance - poorer luminescence (as in amorphous silicon solar cells) reduces both the quantum efficiency (current collected) and also the cell voltage."

Scientists say that this new paper sets expectations for yet higher solar cell performance from this class of perovskite semiconductors. Solar cells are being scaled up for commercial deployment by the Oxford spin-out, Oxford PV Ltd. The efficient luminescence itself may lead to other exciting applications with much broader commercial prospects - a big challenge that the Oxford and Cambridge teams have identified is to construct an electrically driven laser.

####

For more information, please click here

Contacts:
Nalin Patel

44-122-376-0302

Copyright © University of Cambridge

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

New non-invasive method can detect Alzheimer's disease early: MRI probe technology shows brain toxins in living animals for first time December 22nd, 2014

Piezoelectricity in a 2-D semiconductor: Berkeley Lab researchers discovery of piezoelectricty in molybdenum disulfide holds promise for future MEMS December 22nd, 2014

Quantum physics just got less complicated December 22nd, 2014

Enzyme Biosensor Used for Rapid Measurement of Drug December 22nd, 2014

Discoveries

Mysteries of ‘Molecular Machines’ Revealed: Phenix software uses X-ray diffraction spots to produce 3-D image December 22nd, 2014

New non-invasive method can detect Alzheimer's disease early: MRI probe technology shows brain toxins in living animals for first time December 22nd, 2014

Piezoelectricity in a 2-D semiconductor: Berkeley Lab researchers discovery of piezoelectricty in molybdenum disulfide holds promise for future MEMS December 22nd, 2014

Enzyme Biosensor Used for Rapid Measurement of Drug December 22nd, 2014

Announcements

New non-invasive method can detect Alzheimer's disease early: MRI probe technology shows brain toxins in living animals for first time December 22nd, 2014

Piezoelectricity in a 2-D semiconductor: Berkeley Lab researchers discovery of piezoelectricty in molybdenum disulfide holds promise for future MEMS December 22nd, 2014

Quantum physics just got less complicated December 22nd, 2014

Enzyme Biosensor Used for Rapid Measurement of Drug December 22nd, 2014

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

New non-invasive method can detect Alzheimer's disease early: MRI probe technology shows brain toxins in living animals for first time December 22nd, 2014

Piezoelectricity in a 2-D semiconductor: Berkeley Lab researchers discovery of piezoelectricty in molybdenum disulfide holds promise for future MEMS December 22nd, 2014

Quantum physics just got less complicated December 22nd, 2014

Enzyme Biosensor Used for Rapid Measurement of Drug December 22nd, 2014

Energy

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

How does enzymatic pretreatment affect the nanostructure and reaction space of lignocellulosic biomass? December 18th, 2014

Iranian Scientists Use Nanotechnology to Increase Power, Energy of Supercapacitors December 18th, 2014

Lifeboat Foundation gives 2014 Guardian Award to Elon Musk December 16th, 2014

Photonics/Optics/Lasers

Scientists reveal breakthrough in optical fiber communications December 21st, 2014

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Nanoshaping method points to future manufacturing technology December 11th, 2014

Stacking two-dimensional materials may lower cost of semiconductor devices December 11th, 2014

Solar/Photovoltaic

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Lifeboat Foundation gives 2014 Guardian Award to Elon Musk December 16th, 2014

Stacking two-dimensional materials may lower cost of semiconductor devices December 11th, 2014

New Technique Could Harvest More of the Sun's Energy December 9th, 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