. 24/7 Space News .
CARBON WORLDS
Nanodiamonds as photocatalysts
by Staff Writers
Berlin, Germany (SPX) Oct 19, 2018

Doped diamond foam.

Climate change is in full swing and will continue unabated as long as we do not succeed in significantly reducing CO2 emissions. For this we need all the options. One idea is to return the greenhouse gas CO2 to the energy cycle: CO2 could be processed with water into methanol, a fuel that can be excellently transported and stored.

However, the reaction, which is reminiscent of a partial process of photosynthesis, requires energy and catalysts. If we succeed in using this energy from sunlight and developing light-active photocatalysts that are not made of rare metals such as platinum, but of inexpensive and abundantly available materials, there would be a chance of "green" solar fuels being produced in a climate-neutral way.

Diamond Nanomaterials need UV for activation
A candidate for such photocatalysts are so-called diamond nanomaterials - these are not precious crystalline diamonds, but tiny nanocrystals of a few thousand carbon atoms that are soluble in water and look more like black slurry, or nanostructured "carbon foams" with high surface area.

In order for these materials to become catalytically active, however, they require UV light excitation. Only this spectral range of sunlight is rich enough in energy to transport electrons from the material into a "free state". Only then solvated electrons can be emitted in water and react with the dissolved 2 to form methanol.

Can doping help?
However, the UV component in the solar spectrum is not very high. Photocatalysts that could also use the visible spectrum of sunlight would be ideal. This is where the work of HZB-scientist Tristan Petit and his cooperation partners in DIACAT comes in: modelling the energy levels in such materials, performed by Karin Larsson in Uppsala University, shows that intermediate stages can be built into the band gap by doping with foreign atoms. Boron, a trivalent element, appears to be particularly important.

Experiments at BESSY II show: yes, but...
Petit and his team therefore investigated samples of polycrystalline diamonds, diamond foams and nanodiamonds. These samples had previously been synthesized in the groups of Anke Kruger in Wurzburg and Christoph Nebel in Freiburg. At BESSY II, X-ray absorption spectroscopy was used to precisely measure the unoccupied energy states where electrons could possibly be excited by visible light.

"The boron atoms present near the surface of these nanodiamonds actually lead to the desired intermediate stages in the band gap," explains Ph.D student Sneha Choudhury, first author of the study. These intermediate stages are typically very close to the valence bands and thus do not allow the effective use of visible light. However, the measurements show that this also depends on the structure of the nanomaterials.

Outlook: Morphology and doping with P or N
"We can introduce and possibly control such additional steps in the diamond bandgap by specifically modifying the morphology and doping," says Tristan Petit. Doping with phosphorus or nitrogen could also offer new opportunities.

Research paper


Related Links
Helmholtz-Zentrum Berlin fur Materialien und Energie
Carbon Worlds - where graphite, diamond, amorphous, fullerenes meet


Thanks for being there;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Monthly Supporter
$5+ Billed Monthly


paypal only
SpaceDaily Contributor
$5 Billed Once


credit card or paypal


CARBON WORLDS
Exploring new spintronics device functionalities in graphene heterostructures
London, UK (SPX) Oct 17, 2018
Graphene Flagship researchers have shown in a paper published in Science Advances how heterostructures built from graphene and topological insulators have strong, proximity induced spin-orbit coupling which can form the basis of novel information processing technologies. Spin-orbit coupling is at the heart of spintronics. Graphene's spin-orbit coupling and high electron mobility make it appealing for long spin coherence length at room temperature. Graphene Flagship researchers showed a stron ... read more

Comment using your Disqus, Facebook, Google or Twitter login.



Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

CARBON WORLDS
Plant hormone makes space farming a possibility

Installing life support the hands-free way

Smell and stress sensors a smash at Tokyo tech fair

Escape capsule with Soyuz MS-10 crew hit ground 5 times before stopping

CARBON WORLDS
US astronaut Hague 'amazed' by Russian rescue team's work after Soyuz failure

Russian investigators identify responsible for failed Soyuz launch

Russian Space Corp gets telemetry data, video to probe Soyuz failure

Roscosmos plans to restart Soyuz launches from late November

CARBON WORLDS
The claw game on Mars: NASA InSight plays to win

Scientists to debate landing site for next Mars rover

Efforts to communicate with Opportunity continue

Painting cars for Mars

CARBON WORLDS
China's commercial aerospace companies flourishing

China launches Centispace-1-s1 satellite

China tests propulsion system of space station's lab capsules

China unveils Chang'e-4 rover to explore Moon's far side

CARBON WORLDS
How Max Polyakov from Zaporozhie develops the Ukrainian space industry

European Space Talks: we need more space!

Source reveals timing of OneWeb satellites' debut launch on Soyuz

French Space Agency opens new office in the UAE

CARBON WORLDS
Bursting the clouds for better communication

Lockheed Martin reaches technical milestone for Long Range Discrimination Radar

Extremely small magnetic nanostructures with invisibility cloak imaged

Kleos Space signs MoU with Airbus to collaborate on In-Space manufacturing technology

CARBON WORLDS
Double dust ring test could spot migrating planets

Life-long space buff and Western graduate student discovers exoplanet

How the seeds of planets take shape

NASA should expand search for life in the universe: NAS Report

CARBON WORLDS
Icy moon of Jupiter, Ganymede, shows evidence of past strike-slip faulting

Icy warning for space missions to Jupiter's moon

New Horizons sets up for New Year's flyby of Ultima Thule

Hunt for Planet X reveals the Goblin, a faraway dwarf planet









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.