Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A Nanosized Hydrogen Generator

22.09.2014

Researchers at the U.S. Department of Energy’s (DOE) Argonne National Laboratory have created a small scale “hydrogen generator” that uses light and a two-dimensional graphene platform to boost production of the hard-to-make element.

The research also unveiled a previously unknown property of graphene. The two-dimensional chain of carbon atoms not only gives and receives electrons, but can also transfer them into another substance.


John Lambert

Hydrogen Generator. Argonne researchers produce trace amounts of hydrogen with visible light by merging light-collecting proteins from a single-celled organism with a graphene platform. Both graphene and protein absorb the light and re-direct electrons towards the titanium dioxide. Electrons interact with protons at the site of the platinum nanoparticles to produce hydrogen.

Hydrogen is virtually everywhere on the planet, but the element is typically bonded with other elements and must be separated from oxygen in H2O to produce free hydrogen. The commercial separation process uses natural gas to react with superheated steam to strip away hydrogen atoms producing hydrogen fuel, but also carbon dioxide —a greenhouse gas byproduct which escapes into the atmosphere.

Argonne’s early-stage generator, composed of many tiny assemblies, is proof that hydrogen can be produced without burning fossil fuels. The scale is small, a little smaller than the diameter of spider silk. Scaling this research up in the future may mean that you could replace the gas in your cars and generators with hydrogen—a greener option, because burning hydrogen fuel emits only water vapor.

“Many researchers are looking to inorganic materials for new sources of energy,” said Elena Rozhkova, chemist at Argonne’s Center for Nanoscale Materials, a DOE Office of Science (Office of Basic Energy Sciences) User Facility. “Our goal is to learn from the natural world and use its materials as building blocks for innovation.”

For Rozhkova, this particular building block is inspired by the function of an ancient protein known to turn light into energy. Researchers have long known that some single-celled organisms use a protein called bacteriorhodopsin (bR) to absorb sunlight and pump protons through a membrane, creating a form of chemical energy. They also know that water can be split into oxygen and hydrogen by combining these proteins with titanium dioxide and platinum and then exposing them to ultraviolet light.

There is just one downside: titanium dioxide only reacts in the presence of ultraviolet light, which makes up a mere four percent of the total solar spectrum. If the researchers wanted to power their generators with sunlight, they’d need to improve on that.

In order to produce greater amounts of hydrogen using visible light, the researchers looked for a new material. The new material would need enough surface area to move electrons across quickly and evenly and boost the overall electron transfer efficiency. The researchers also needed a platform on which biological components, like bR, could survive and connect with the titanium dioxide catalyst: in short, a material like graphene.

Graphene is a super strong, super light, near totally transparent sheet of carbon atoms and one of the best conductors of electricity ever discovered. Graphene owes its amazing properties to being two-dimensional.

“Graphene not only has all these amazing properties, but it is also ultra-thin and biologically inert,” said Rozhkova. “Its very presence allowed the other components to self-assemble around it, which totally changes how the electrons move throughout our system.”

Rozhkova’s mini-hydrogen generator works like this: both the bR protein and the graphene platform absorb visible light. Electrons from this reaction are transmitted to the titanium dioxide on which these two materials are anchored, making the titanium dioxide sensitive to visible light.

Simultaneously, light from the green end of the solar spectrum triggers the bR protein to begin pumping protons along its membrane. These protons make their way to the platinum nanoparticles which sit on top of the titanium dioxide. Hydrogen is produced by the interaction of the protons and electrons as they converge on the platinum.

Examinations using a technique called Electron Paramagnetic Resonance (EPR) and time-resolved spectroscopy at the Center for Nanoscale Materials verified the movements of the electrons within the system, while electrochemical studies confirmed the protons were transferred. Tests also revealed a new quirk of graphene behavior.

“The majority of the research out there states that graphene principally conducts and accepts electrons,” said Argonne postdoctoral researcher Peng Wang. “Our exploration using EPR allowed us to prove, experimentally, that graphene also injects electrons into other materials.”

Rozhkova’s hydrogen generator proves that nanotechnology, merged with biology, can create new sources of clean energy. Her team’s discovery may provide future consumers a biologically-inspired alternative to gasoline.

“These are the types of discoveries we can make at Argonne,” said Rozhkova. “Working in the basic energy sciences, we were able to demonstrate an energy-rich biologically-inspired alternative to gas.”

This research, “Photoinduced Electron Transfer pathways in Hydrogen-Evolving Reduced Graphene Oxide-Boosted Hybrid Nano-Bio Catalyst,” appeared in the July 7 issue of ACS Nano. The research was performed at the Center for Nanoscale Materials and supported by the U.S. Department of Energy’s Office of Science.

# # #

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

Justin H. S. Breaux | newswise

More articles from Materials Sciences:

nachricht Watching atoms move in hybrid perovskite crystals reveals clues to improving solar cells
22.11.2017 | University of California - San Diego

nachricht Fine felted nanotubes: CAU research team develops new composite material made of carbon nanotubes
22.11.2017 | Christian-Albrechts-Universität zu Kiel

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

UCLA engineers use deep learning to reconstruct holograms and improve optical microscopy

22.11.2017 | Medical Engineering

Watching atoms move in hybrid perovskite crystals reveals clues to improving solar cells

22.11.2017 | Materials Sciences

New study points the way to therapy for rare cancer that targets the young

22.11.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>