Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Weak light can now be used for applications as well - FOM focus group harvests infrared light

Diagram of the nanocrystal with infrared-absorbing antennae. NIR = near infrared, ET = energy transfer, VIS = emission of visible light.
Diagram of the nanocrystal with infrared-absorbing antennae. NIR = near infrared, ET = energy transfer, VIS = emission of visible light.

Abstract:
Chemists and materials scientists from the University of Groningen and the FOM Foundation have found a way of ‘harvesting‘ infrared light more efficiently. For this they use special molecules, which act as light antennae to capture the energy from weak infrared light. The antennae transmit the energy to the nanoparticles they are attached to. These particles subsequently convert two weak captured photons into a single strong, energy-rich photon, a process termed upconversion. The new antennae molecules amplify this process 3300 times, which represents a considerable improvement for solar cells or medical imaging techniques, for example. The research was published on 15 July 2012 on the website of the journal Nature Photonics.

Weak light can now be used for applications as well - FOM focus group harvests infrared light

Groningen, The Netherlands | Posted on July 17th, 2012

Infrared light has too little energy to release electrons in solar cells, for example. This relatively weak light is therefore lost. One possible way of still being able to use infrared light is ‘upconversion': ‘adding up' the energy of two weak photons to produce a single stronger photon (visible light).

Factor of 3300 increase

"There are inorganic materials made from rare earth metals that can facilitate this upconversion process," explains University of Groningen Professor of Organic Chemistry Kees Hummelen, who leads the FOM-focus group 'Next generation organic photovoltaics'. "However these materials absorb very few infrared photons. We have therefore attached organic molecules to them as antennae that can capture these photons and transmit the energy to the upconversion material. With this, the entire process of infrared absorption, upconversion and the emission of visible light is being increased by a factor of 3300."

Harvest

Hummelen's group is trying to further increase the harvest of infrared photons. "Even with our antennae we still only capture a limited amount of the infrared light. And even better yield can be obtained," predicts Hummelen. However the process of upconversion inside the nanocrystal is still rather inefficient. "Two photons must come together in the material within a short space of time. In practice the efficiency of this process is still very low. However the harvest is already much better, so step 1 has been achieved!" says Hummelen. Therefore, the work of the researchers in Groningen is mainly a proof that infrared photons can be harvested by means of upconversion.

Solar cells

The most obvious application is in solar cells, as about half of all the solar energy reaching the Earth's surface consists of infrared light. "A German group is going to incorporate our nanocrystals with antennae in solar cells to test these in practice," says Hummelen, who since last year has led a FOM focus group researching the new generation of organic solar cells. By capturing more infrared light, solar cells will be able to pass the so-called Shockley-Queisser efficiency limit. For solar cells that consist of one color that limit is 32 percent.

Medical images

The system for upconversion of infrared light also has other applications, including medical imaging techniques. "Infrared light penetrates further into biological tissues than visible light. If you allow compounds that carry out upconversion to bind to specific cells in tissues then you can make images using infrared light," explains Hummelen.

Worlds combined

In the FOM focus group at the University of Groningen researchers combine organic and inorganic chemistry. "These worlds are usually still quite distinct," says Hummelen. "We have brought them together, with this success as the result." They modified an organic dye that can absorb infrared light so that this could be attached as an antenna to a lanthanide nanocrystal. About 60 of these antennae are attached to a single crystal. "If you try to place more on the crystal then they disrupt each other." The antennae capture the infrared energy and transmit it to the nanocrystal, which subsequently uses it to produce energy-richer photons that have enough energy to release an electron in solar cells, for example. "Our inspiration partly came from the photosynthesis complex of plants," explains Hummelen. "There you have a ring of light-absorbing molecules around an active centre."

Zernike Institute for Advanced Materials

The research was largely carried out by FOM PhD student Wenqiang Zou, masters student Jeremio Maduro and postdoc Cindy Visser and took place at the Stratingh Institute for Chemistry and the Zernike Institute for Advanced Materials (ZIAM), both part of the Faculty of Mathematics and Natural Sciences at the University of Groningen. Kees Hummelen and Maxim Pchenitchnikov supervised the work.

Full bibliographic informationNature Photonics, DOI 10.1038/nphoton.2012.158
Broadband Dye-Sensitized Upconversion of Near-IR Light , Wenqiang Zou1, Cindy Visser1, Jeremio A.Maduro1, Maxim S. Pshenichnikov2 and Jan C. Hummelen1,2*, 1Stratingh Institute for Chemistry, University of Groningen, 2Zernike Institute for Advanced Materials, University of Groningen, The Netherlands, Nature Photonics, DOI 10.1038/nphoton.2012.158

####

About University of Groningen
The University of Groningen enjoys an international reputation as a leading research university. The university is utilizing its academic heritage to generate innovation, with the help of cutting-edge facilities. In a work environment that rewards quality and achievement, the university offers balanced study and research paths that vary in intensity to encourage everyone to draw on their individual talents.

For more information, please click here

Contacts:
Fenneke Colstee


Prof. J.C. (Kees) Hummelen

phone +31 50 363 5553
or
dr. M.S. Pchenitchnikov

phone +31 50 363 4159

Copyright © AlphaGalileo

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

Imaging

New technique for exploring structural dynamics of nanoworld: Developed in a Nobel laureate's laboratory at Caltech, hybrid approach allows ultrafast EM analysis of materials, showing tiny electronic changes in individual atoms within a material on ultrafast time scales April 28th, 2015

News and information

New technique for exploring structural dynamics of nanoworld: Developed in a Nobel laureate's laboratory at Caltech, hybrid approach allows ultrafast EM analysis of materials, showing tiny electronic changes in individual atoms within a material on ultrafast time scales April 28th, 2015

When mediated by superconductivity, light pushes matter million times more April 28th, 2015

Chemists strike nano-gold: 4 new atomic structures for gold nanoparticle clusters: Research builds upon work by Nobel Prize-winning team from Stanford University April 28th, 2015

Self-assembling biomaterial forms nanostructure templates for human tissue formation April 27th, 2015

Discoveries

New technique for exploring structural dynamics of nanoworld: Developed in a Nobel laureate's laboratory at Caltech, hybrid approach allows ultrafast EM analysis of materials, showing tiny electronic changes in individual atoms within a material on ultrafast time scales April 28th, 2015

When mediated by superconductivity, light pushes matter million times more April 28th, 2015

Chemists strike nano-gold: 4 new atomic structures for gold nanoparticle clusters: Research builds upon work by Nobel Prize-winning team from Stanford University April 28th, 2015

More is less in novel electronic material: Adding electrons actually shrinks the system April 27th, 2015

Announcements

New technique for exploring structural dynamics of nanoworld: Developed in a Nobel laureate's laboratory at Caltech, hybrid approach allows ultrafast EM analysis of materials, showing tiny electronic changes in individual atoms within a material on ultrafast time scales April 28th, 2015

When mediated by superconductivity, light pushes matter million times more April 28th, 2015

Chemists strike nano-gold: 4 new atomic structures for gold nanoparticle clusters: Research builds upon work by Nobel Prize-winning team from Stanford University April 28th, 2015

Sensor Designed in Iran Able to Remove Formaldehyde Gas from Environment April 27th, 2015

Energy

Pseudoparticles travel through photoactive material: KIT scientists measure important process in the conversion of light energy -- publication in Nature Communications April 24th, 2015

Scientists Use Nanoscale Building Blocks and DNA 'Glue' to Shape 3D Superlattices: New approach to designing ordered composite materials for possible energy applications April 23rd, 2015

'Holey' graphene for energy storage: Charged holes in graphene increase energy storage capacity April 22nd, 2015

Expanding the reach of metallic glass April 22nd, 2015

Research partnerships

When mediated by superconductivity, light pushes matter million times more April 28th, 2015

Chemists strike nano-gold: 4 new atomic structures for gold nanoparticle clusters: Research builds upon work by Nobel Prize-winning team from Stanford University April 28th, 2015

International research team discovers new mechanism behind malaria progression: Findings provide a new avenue for research in malaria treatment April 27th, 2015

More is less in novel electronic material: Adding electrons actually shrinks the system April 27th, 2015

Solar/Photovoltaic

Pseudoparticles travel through photoactive material: KIT scientists measure important process in the conversion of light energy -- publication in Nature Communications April 24th, 2015

Printing Silicon on Paper, with Lasers April 21st, 2015

Better battery imaging paves way for renewable energy future April 20th, 2015

The microscopic topography of ink on paper: Researchers have analyzed the varying thickness of printed toner in unprecedented 3-D detail, yielding insights that could lead to higher quality, less expensive and more environmentally-friendly glossy and non-glossy papers April 14th, 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