Featured Research

from universities, journals, and other organizations

Plugging In Molecular Wires To Capture Light Energy

Date:
February 17, 2009
Source:
Wiley-Blackwell
Summary:
Japanese researchers have developed a new process to capture light energy -- they "plug" a molecular "wire" directly into a biological photosynthetic system to efficiently conduct the free electrons to a gold electrode.

The secret to the success of natural photosystems is the perfect fit of the individual components. The molecules fit precisely together like plugs and sockets and can pass electrons on directly and nearly without loss.
Credit: Copyright Wiley-VCH

Plants, algae, and cyanobacteria (blue-green algae) are masters of everything to do with solar energy because they are able to almost completely transform captured sunlight into chemical energy. This is in part because the electrons set free by the photons are transported out of the “light receptor” 1:1 to be used as the driving force for chemical reactions.

Japanese researchers have now developed a new process to capture light energy with nearly equal efficiency. As they report in the journal Angewandte Chemie, they “plug” a molecular “wire” directly into a biological photosynthetic system to efficiently conduct the free electrons to a gold electrode.

The efficiency of photovoltaic energy conversion is of critical significance for the practical application of solar installations. Theoretically, every photon absorbed should release one electron. Whereas modern solar cells are far from achieving high efficiency, natural photosynthetic systems achieve nearly 100 % quantum yield. To improve the efficiency of synthetic systems, experiments were attempted in which biological light-capturing units were deposited onto electrodes as thin films. However, the transfer of electrons from the light-capturing layer into the circuit in this type of system is so inefficient that most of the electrons don’t even make it to the target electrode.

The secret to the success of natural photosystems is the perfect fit of the individual components. The molecules fit precisely together like plugs and sockets and can pass electrons on directly and nearly without loss. The new approach taken by the Japanese researchers cleverly connects photosystem I (PSI) from the blue-green algae Thermosynechococcus elongatus with a synthetic apparatus. An important component of the electron transmission sequence of PSI is vitamin K1. The researchers removed the vitamin K1 from the PSI protein complex and replaced it with a synthetic analogue.

This consists of three parts:

  1. The same molecular “plug” with which vitamin K1 is bound to the protein complex (napthoquinone group) is used to “plug in” the synthetic binding component to PSI;
  2. a molecular “wire” (hydrocarbon chain) with the same length as in vitamin K1 ensures that the binding component protrudes from the protein complex; and
  3. at the other end of the wire is an additional “plug” (viologen group) that anchors the ensemble to a specially coated gold electrode.

Electrons released by irradiation of PSI and transmitted along the wire are very efficiently transmitted to the gold electrode by the viologen group.

It may be possible to use this new strategy to integrate other biocomponents into synthetic systems.


Story Source:

The above story is based on materials provided by Wiley-Blackwell. Note: Materials may be edited for content and length.


Journal Reference:

  1. Nao Terasaki. Plugging a Molecular Wire into Photosystem I: Reconstitution of the Photoelectric Conversion System on a Gold Electrode. Angewandte Chemie International Edition, 2009, 48, 1585%u20131587 DOI: 10.1002/anie.200805748

Cite This Page:

Wiley-Blackwell. "Plugging In Molecular Wires To Capture Light Energy." ScienceDaily. ScienceDaily, 17 February 2009. <www.sciencedaily.com/releases/2009/02/090212112736.htm>.
Wiley-Blackwell. (2009, February 17). Plugging In Molecular Wires To Capture Light Energy. ScienceDaily. Retrieved April 20, 2014 from www.sciencedaily.com/releases/2009/02/090212112736.htm
Wiley-Blackwell. "Plugging In Molecular Wires To Capture Light Energy." ScienceDaily. www.sciencedaily.com/releases/2009/02/090212112736.htm (accessed April 20, 2014).

Share This



More Matter & Energy News

Sunday, April 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Why Did Nike Fire Most Of Its Nike FuelBand Team?

Why Did Nike Fire Most Of Its Nike FuelBand Team?

Newsy (Apr. 19, 2014) Nike fired most of its Digital Sport hardware team, the group behind Nike's FuelBand device. Could Apple or an overcrowded market be behind layoffs? Video provided by Newsy
Powered by NewsLook.com
Small Reactors Could Be Future of Nuclear Energy

Small Reactors Could Be Future of Nuclear Energy

AP (Apr. 17, 2014) After the Fukushima nuclear disaster, the industry fell under intense scrutiny. Now, small underground nuclear power plants are being considered as the possible future of the nuclear energy. (April 17) Video provided by AP
Powered by NewsLook.com
Horseless Carriage Introduced at NY Auto Show

Horseless Carriage Introduced at NY Auto Show

AP (Apr. 17, 2014) An electric car that proponents hope will replace horse-drawn carriages in New York City has also been revealed at the auto show. (Apr. 17) Video provided by AP
Powered by NewsLook.com
Honda's New ASIMO Robot, More Human-Like Than Ever

Honda's New ASIMO Robot, More Human-Like Than Ever

AFP (Apr. 17, 2014) It walks and runs, even up and down stairs. It can open a bottle and serve a drink, and politely tries to shake hands with a stranger. Meet the latest ASIMO, Honda's humanoid robot. Duration: 00:54 Video provided by AFP
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