Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Liquid crystals line up to make self-healing photovoltaic device

Figure 1: Schematic of the liquid crystal molecule (top) and the formed liquid crystal photovoltaic device (bottom). Purple spheres represent the fullerene and yellow/green chains the oligothiophene, the hydrophobic/hydrophilic tails are represented by blue/red lines respectively. Image:Riken
Figure 1: Schematic of the liquid crystal molecule (top) and the formed liquid crystal photovoltaic device (bottom). Purple spheres represent the fullerene and yellow/green chains the oligothiophene, the hydrophobic/hydrophilic tails are represented by blue/red lines respectively. Image:Riken

Abstract:
Molecules containing both electron donors and acceptors have been functionalized with tails that control their arrangement in a liquid-crystal photovoltaic device

Liquid crystals line up to make self-healing photovoltaic device

Japan | Posted on October 31st, 2008

A huge market is developing for small disposable electronic devices, ranging from security tags to point-of-care diagnostics. Many of these devices require a power source, and photovoltaic devices (solar cells) are an attractive option. However, the expense of preparing and processing inorganic semiconductors used in traditional solar cells precludes their use in such applications. Organic photovoltaic devices, meanwhile have great potential in this area; they are relatively easy to prepare and can be processed by simple techniques such as inkjet printing.

Organic photovoltaic devices contain both electron donors, which release an electron when irradiated, and electron acceptors, which complete the circuit necessary to convert light energy into electrical energy. However, mixtures of typical electron donors such as π-conjugated oligomers—short chains of repeated, unsaturated, organic molecules, with alternating double and single bonds—and electron acceptors, such as C60 (buckminsterfullerene), have a tendency to form alternating stacks that results in lower efficiency. A partial solution is to directly attach the electron donor to the electron acceptor by a covalent bond and have both in a single molecule, but it is still important to have control over how the molecules pack together.

Now, a team of Japanese researchers including Takuzo Aida from the University of Tokyo and Masaki Takata from the RIKEN SPring-8 Center in Harima have designed liquid crystals—a phase that flows like a liquid but has short-range order between the molecules—that spontaneously assemble to form a donor-acceptor array1. "It's important to form separated columns or layers of the donors and acceptors, and to make a large contact area between them," explains Yohei Yamamoto, another member of the team from the Japan Science and Technology Agency in Tokyo.

The molecules they designed feature a fullerene—the electron acceptor—at one end and a thiophene oligomer—the electron donor—at the other. A hydrophobic, or water-repellent, tail is attached to the donor end and a hydrophilic, or water-loving, tail is attached to the acceptor end. This functionalization ensures that the molecules of the liquid crystal line up (Fig. 1) to produce ordered layers of donors and acceptors and results in efficient photovoltaic behavior. "The liquid characteristics are useful as well," notes Yamamoto, "the devices are self-healing as defects in the layer structure can be repaired by a simple heating and cooling process." The design principles developed in this work should lead to the development of high-efficiency organic photovoltaic devices.
Reference

1. Li, W.-S., Yamamoto, Y., Fukushima, T., Saeki, A., Seki, S., Tagawa, S., Masunaga, H., Sasaki, S., Takata, M. & Aida, T. Amphiphilic molecular design as a rational strategy for tailoring bicontinuous electron donor and acceptor arrays: photoconductive liquid crystalline oligothiophene-C60 dyads. Journal of the American Chemical Society 130, 8886-8887 (2008).

The corresponding author for this highlight is based at the RIKEN Structural Materials Science Laboratory

####

For more information, please click here

Copyright © Riken

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 Links

article

Related News Press

News and information

A nanoscale wireless communication system via plasmonic antennas: Greater control affords 'in-plane' transmission of waves at or near visible light August 27th, 2016

Forces of nature: Interview with microscopy innovators Gerd Binnig and Christoph Gerber August 26th, 2016

A promising route to the scalable production of highly crystalline graphene films August 26th, 2016

Graphene under pressure August 26th, 2016

Discoveries

A promising route to the scalable production of highly crystalline graphene films August 26th, 2016

Graphene under pressure August 26th, 2016

Nanofur for oil spill cleanup: Materials researchers learn from aquatic ferns: Hairy plant leaves are highly oil-absorbing / publication in bioinspiration & biomimetics / video on absorption capacity August 25th, 2016

Unraveling the crystal structure of a -70° Celsius superconductor, a world first: Significant advancement in the realization of room-temperature superconductors August 25th, 2016

Announcements

A nanoscale wireless communication system via plasmonic antennas: Greater control affords 'in-plane' transmission of waves at or near visible light August 27th, 2016

Forces of nature: Interview with microscopy innovators Gerd Binnig and Christoph Gerber August 26th, 2016

A promising route to the scalable production of highly crystalline graphene films August 26th, 2016

Graphene under pressure August 26th, 2016

Energy

New electrical energy storage material shows its power: Nanomaterial combines attributes of both batteries and supercapacitors August 25th, 2016

Lehigh engineer discovers a high-speed nano-avalanche: New findings published in the Journal of Electrochemical Society about the process involving transformations in glass that occur under intense electrical and thermal conditions could lead the way to more energy-efficient glas August 24th, 2016

New flexible material can make any window 'smart' August 23rd, 2016

Researchers reduce expensive noble metals for fuel cell reactions August 22nd, 2016

Solar/Photovoltaic

Let's roll: Material for polymer solar cells may lend itself to large-area processing: 'Sweet spot' for mass-producing polymer solar cells may be far larger than dictated by the conventional wisdom August 12th, 2016

NREL technique leads to improved perovskite solar cells August 11th, 2016

Making a solar energy conversion breakthrough with help from a ferroelectrics pioneer: Philadelphia-based team shows how a ferroelectric insulator can surpass shockley-queisser limit August 9th, 2016

Tiny high-performance solar cells turn power generation sideways August 5th, 2016

Printing/Lithography/Inkjet/Inks

Tailored probes for atomic force microscopes: 3-D laser lithography enhances microscope for studying nanostructures in biology and engineering/ publication in Applied Physics Letters August 11th, 2016

Smarter self-assembly opens new pathways for nanotechnology: Brookhaven Lab scientists discover a way to create billionth-of-a-meter structures that snap together in complex patterns with unprecedented efficiency August 9th, 2016

Nanoscientists develop the 'ultimate discovery tool': Rapid discovery power is similar to what gene chips offer biology June 25th, 2016

Perovskite solar cells surpass 20 percent efficiency: EPFL researchers are pushing the limits of perovskite solar cell performance by exploring the best way to grow these crystals June 13th, 2016

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







Car Brands
Buy website traffic