Getting energy from sunlight: Plants have it down; humans have not quite got the knack for it. Hybrid systems made from natural and synthetic components could open new routes for harvesting solar energy.
Italian researchers have now introduced an approach to this type of system. As described in the journal Angewandte Chemie, they have combined the photochemical core of a bacterial photosynthetic system with an organic dye that acts as an “antenna”, significantly improving the capture of light.
In all organisms fuelled by photosynthesis, the functional organization of the photosynthetic apparatus is the same: pigment-protein complexes capture the light like a radio antenna catching radio waves and conduct it to a central photochemical core, the reaction center. Here the energy is converted to an electron-hole pair: a negatively charged electron is separated from its molecular core, leaving behind a positively charged “hole”.
This charge-separated state must be maintained long enough to be used. The organism uses this to drive its metabolism. In technological applications, charge separation may be used to drive a redox reaction like the splitting of water into hydrogen and oxygen.
Nature has optimal control over these steps. Synthetic systems that efficiently capture light and use the energy to achieve charge separation have also been developed; however the lifetime of the charge separation is barely in the millisecond range. This is not enough to allow the energy to be drawn off efficiently. An interesting approach to solving this problem is to make hybrid systems that combine a tailored synthetic antenna with a natural “light converter”. Previously, synthetic antennas have been made from quantum dots, nanoscopic structures made of semiconductors.
Instead, researchers led by Gianluca M. Farinola and Massimo Trotta have elected to use a tailored organic dye molecule as their antenna. These have several advantages over inorganic structures: The molecular diversity of organic compounds allows for very fine tuning of the spectroscopic and electronic properties of the antenna. At the same time, the molecular form and flexibility can be controlled so that the antenna has practically no effect on the reaction center and its function, unlike quantum dots. An organic antenna can also be attached to nearly any desired location on the reaction center.
The Italian researchers combined their organic antenna with the extensively researched reaction center of the purple bacterium Rhodobacter sphaeroides R-26. They demonstrated that the antenna does not disrupt the function of the natural light converted; instead it improves its activity in a range of wavelengths not efficiently absorbed by the purely biological system.About the Author
Angewandte Chemie International Edition 2012, 51, No. 44, 11019–11023, Permalink to the article: http://dx.doi.org/10.1002/anie.201203404
Dr Massimo Trotta | Angewandte Chemie
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences