Navigation Links
'Tall order' sunlight-to-hydrogen system works, neutron analysis confirms
Date:2/3/2011

OAK RIDGE, Tenn. Feb. 3, 2011 -- Researchers at the Department of Energy's Oak Ridge National Laboratory have developed a biohybrid photoconversion system -- based on the interaction of photosynthetic plant proteins with synthetic polymers -- that can convert visible light into hydrogen fuel.

Photosynthesis, the natural process carried out by plants, algae and some bacterial species, converts sunlight energy into chemical energy and sustains much of the life on earth. Researchers have long sought inspiration from photosynthesis to develop new materials to harness the sun's energy for electricity and fuel production.

In a step toward synthetic solar conversion systems, the ORNL researchers have demonstrated and confirmed with small-angle neutron scattering analysis that light harvesting complex II (LHC-II) proteins can self-assemble with polymers into a synthetic membrane structure and produce hydrogen.

The researchers envision energy-producing photoconversion systems similar to photovoltaic cells that generate hydrogen fuel, comparable to the way plants and other photosynthetic organisms convert light to energy.

"Making a, self-repairing synthetic photoconversion system is a pretty tall order. The ability to control structure and order in these materials for self-repair is of interest because, as the system degrades, it loses its effectiveness," ORNL researcher Hugh O'Neill, of the lab's Center for Structural Molecular Biology, said.

"This is the first example of a protein altering the phase behavior of a synthetic polymer that we have found in the literature. This finding could be exploited for the introduction of self-repair mechanisms in future solar conversion systems," he said.

Small angle neutron scattering analysis performed at ORNL's High Flux Isotope Reactor (HFIR) showed that the LHC-II, when introduced into a liquid environment that contained polymers, interacted with polymers to form lamellar sheets similar to those found in natural photosynthetic membranes.

The ability of LHC-II to force the assembly of structural polymers into an ordered, layered state -- instead of languishing in an ineffectual mush -- could make possible the development of biohybrid photoconversion systems. These systems would consist of high surface area, light-collecting panes that use the proteins combined with a catalyst such as platinum to convert the sunlight into hydrogen, which could be used for fuel.

The research builds on previous ORNL investigations into the energy-conversion capabilities of platinized photosystem I complexes -- and how synthetic systems based on plant biochemistry can become part of the solution to the global energy challenge.

"We're building on the photosynthesis research to explore the development of self-assembly in biohybrid systems. The neutron studies give us direct evidence that this is occurring," O'Neill said.

The researchers confirmed the proteins' structural behavior through analysis with HFIR's Bio-SANS, a small-angle neutron scattering instrument specifically designed for analysis of biomolecular materials.

"Cold source" neutrons, in which energy is removed by passing them through cryogenically chilled hydrogen, are ideal for studying the molecular structures of biological tissue and polymers.

The LHC-II protein for the experiment was derived from a simple source: spinach procured from a local produce section, then processed to separate the LHC-II proteins from other cellular components. Eventually, the protein could be synthetically produced and optimized to respond to light.

O'Neill said the primary role of the LHC-II protein is as a solar collector, absorbing sunlight and transferring it to the photosynthetic reaction centers, maximizing their output. "However, this study shows that LHC-II can also carry out electron transfer reactions, a role not known to occur in vivo," he said.

The research team, which came from various laboratory organizations including its Chemical Sciences Division, Neutron Scattering Sciences Division, the Center for Structural Molecular Biology and the Center for Nanophase Materials Sciences, consisted of O'Neill, William T. Heller, and Kunlun Hong, all of ORNL; Dimitry Smolensky of the University of Tennessee; and Mateus Cardoso, a former postdoctoral researcher at ORNL now of the Laboratio Nacional de Luz Sincrotron in Brazil.

"That's one of the nice things about working at a national laboratory. Expertise is available from a variety of organizations," O'Neill said.


'/>"/>

Contact: Bill Cabage
cabagewh@ornl.gov
865-574-4399
DOE/Oak Ridge National Laboratory
Source:Eurekalert

Related biology news :

1. Caltech-led team creates damage-tolerant metallic glass
2. Climate scientist warns world of widespread suffering if further climate change is not forestalled
3. X-ray crystallography reveals structure of precursor to blood-clotting protein
4. Speed installation of system to monitor vital signs of global ocean, scientists urge
5. Parasite investigations breed 3 Tall Poppies
6. Three-quarters of new solar systems worldwide were installed in the EU in 2009
7. Texas A&M research produces tools to study stallions subfertility
8. Scientists develop sustainable, environmentally friendly potting medium
9. Mother Nature to provide an environmentally friendly method for reducing mosquitoes
10. Innovotech receives funding to advance environmentally friendly agricultural crop protection product
11. Evidence that nanoparticles in sunscreens could be toxic if accidentally eaten
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:11/19/2016)... -- Securus Technologies, a leading provider of civil and ... and monitoring, announced today that it has offered a ... independent technology judge determine who has the largest and ... calling platform, and the best customer service. ... what we do – which clearly is not the ...
(Date:11/17/2016)... it has just released a new white paper authored by Zettar that covers the ... transfer storage solutions. Photo - http://photos.prnewswire.com/prnh/20161116/440463 ... ... ... Setting up a high performance computing or HPC system can be a complicated endeavor ...
(Date:11/15/2016)... 2016  Synthetic Biologics, Inc. (NYSE MKT: SYN), ... the gut microbiome, today announced the pricing of ... its common stock and warrants to purchase 50,000,000 ... to the public of $1.00 per share and ... the offering, excluding the proceeds, if any from ...
Breaking Biology News(10 mins):
(Date:12/4/2016)... , Dec. 3, 2016  In five studies ... Hematology (ASH) Annual Meeting and Exposition in ... engineering methods to improve the delivery of life-saving treatments ... new methods are designed to carry therapies directly to ... most, which could provide a substantial advantage over traditional, ...
(Date:12/2/2016)... , Dec. 2, 2016 Amgen (NASDAQ: ... today announced the submission of a Marketing Authorization Application (MAA) ... biosimilar candidate to Avastin ® (bevacizumab). The companies believe ... the EMA. "The submission of ABP 215 ... to expand our oncology portfolio," said Sean E. Harper ...
(Date:12/2/2016)... ... ... Aerocom Healthcare ( http://www.aerocomhealthcare.com ), representing the global leader ... for tracking and securing medications at booth 676 at the ASHP Midyear Clinical ... a proven solution for tracking medications via its system from pharmacy to nursing ...
(Date:12/2/2016)... ... December 02, 2016 , ... The ... to collaboratively developing improved chemistry, manufacturing and control technologies for the pharmaceutical ... with robust, probe-based sampling. , Online liquid chromatography analysis is becoming ...
Breaking Biology Technology: