NUS graphene researchers create 'superheated' water that can corrode diamonds

Novel discovery paves the way to improve waste degradation and laser-assisted etching of materials

2013-03-11

(Press-News.org) A team of researchers from the National University of Singapore (NUS) led by Professor Loh Kian Ping, Head of the Department of Chemistry at the NUS Faculty of Science, has successfully altered the properties of water, making it corrosive enough to etch diamonds. This was achieved by attaching a layer of graphene on diamond and heated to high temperatures. Water molecules trapped between them become highly corrosive, as opposed to normal water.

This novel discovery, reported for the first time, has wide-ranging industrial applications, from environmentally-friendly degradation of organic wastes to laser-assisted etching of semiconductor or dielectric films.

The findings were published online in Nature Communications on 5 March 2013 with Ms Candy Lim Yi Xuan, a Ph.D. candidate at the NUS Graduate School for Integrative Sciences and Engineering as the first author.

When Diamond Meets Graphene

While diamond is known to be a material with superlative physical qualities, little is known about how it interfaces with graphene, a one-atom thick substance composed of pure carbon.

A team of scientists from NUS, Bruker Singapore and Hasselt University Wetenschapspark in Belgium, sought to explore what happens when a layer of graphene, behaving like a soft membrane, is attached on diamond, which is also composed of carbon. To encourage bonding between the two rather dissimilar carbon forms, the researchers heated them to high temperatures.

At elevated temperatures, the team noted a restructuring of the interface and chemical bonding between graphene and diamond. As graphene is an impermeable material, water trapped between the diamond and graphene cannot escape. At a temperature that is above 400 degree Celsius, the trapped water transforms into a distinct supercritical phase, with different behaviours compared to normal water.

Said Professor Loh, who is also a Principal Investigator with the Graphene Research Centre at NUS, "We show for the first time that graphene can trap water on diamond, and the system behaves like a 'pressure cooker' when heated. Even more surprising, we found that such superheated water can corrode diamond. This has never been reported."

Industrial Applications and New Insights

Due to its transparent nature, the graphene bubble-on-diamond platform provides a novel way of studying the behaviours of liquids at high pressures and high temperature conditions, which is traditionally difficult.

"The applications from our experiment are immense. In the industry, supercritical water can be used for the degradation of organic waste in an environmentally friendly manner. Our work can is also applicable to the laser-assisted etching of semiconductor or dielectric films, where the graphene membrane can be used to trap liquids," Prof Loh elaborated.

To further their research, Prof Loh and his team will study the supercritical behaviours of other fluids at high temperatures, and strive to derive a wider range of industrial applications.

### For more information and scheduling of media interviews, please contact:

Carolyn FONG
Manager (Media relations)
Office of Corporate Relations
National University of Singapore
DID: +65 6516 5399
Email: carolyn@nus.edu.sg

ELSE PRESS RELEASES FROM THIS DATE:

Researchers develop tools for discovering new species

2013-03-11

AMHERST, Mass. – For hundreds of years, naturalists and scientists have identified new species based on an organism's visible differences. But now, new genetic techniques are revealing that different species can show little, to no visible differences. In a just-published study, evolutionary biologists at the University of Massachusetts Amherst and the American Museum of Natural History (AMNH) combine traditional morphological tests plus genetic techniques to describe new species. Groups of morphologically similar organisms that show very divergent genetics are generally ...

DNA barcoding alone sufficient to detect fraudulent deer products

2013-03-11

Many Europeans are fretting these days over what they eat, and whether horse meat might have adulterated their pork chops. Food fraud has been dominating headlines globally - calling for new policies in law enforcement and more robust methods for successful food identification and authentication. As companies and manufacturers resort to fraudulent practices to extract more cash from the gullible public, it is estimated that up to 7% of the consumer supply chain contains hidden ingredients (i.e. – not disclosed on the label). And while all too often policymakers seem oblivious ...

Folic acid lowers risk of autism

2013-03-11

These findings are the result of a new study carried out at the Norwegian Institute of Public Health. In the study, women who took folic acid supplements from four weeks before conception to eight weeks into pregnancy had a 40 per cent lower risk of giving birth to children with childhood autism (classic autism). "It appears that the crucial time interval is from four weeks before conception to eight weeks into pregnancy," states Pål Surén, MD and doctoral fellow at the Norwegian Institute of Public Health. The study is based on the Norwegian Mother and Child Cohort ...

Peer support shows promise in epilepsy fight

2013-03-11

Peer support groups show promise for combating the debilitating stigma that surrounds epilepsy in much of the developing world, according to a new study led by a Michigan State University medical student. The researchers report in the journal Epilepsy and Behavior that young people with the disease felt significantly less stigmatized after meeting regularly to discuss their illness. While drugs are widely available to reduce epileptic seizures, the stigma and discrimination that arise from those seizures is a thornier problem, said Melissa Elafros, who is pursuing medical ...

Symptoms and care of irregular heartbeats differ by gender

2013-03-11

DURHAM, NC – Women with atrial fibrilation have more symptoms and lower quality of life than men with the same heart condition, according to an analysis of patients in a large national registry compiled by the Duke Clinical Research Institute. The finding adds to a growing body of research that highlights gender disparities in how cardiovascular disease is managed, and serves as a caution to doctors to be alert to treatment decisions that might perpetuate the differences. "We need to pay close attention to women with atrial fibrillation, and it's important for physicians ...

Denied the chance to cheat or steal, people turn to violent video games

2013-03-11

COLUMBUS, Ohio – A new study suggests that people get frustrated when they are offered the opportunity to cheat or steal and that chance is then taken away from them. Other studies have shown that blocking people from achieving their positive goals increases frustration, which is not surprising. But this is the first to show that even denying people the chance to commit forbidden behaviors can increase frustration. That's not all. The researchers also found that people who are frustrated in their attempts to cheat or steal are more likely than others to be attracted ...

Pittsburgh's leaky faucet: How aging sewers are impacting urban watersheds

2013-03-11

PITTSBURGH—Aging sewer systems are spilling a considerable amount of nitrogen into urban watersheds, diminishing both the quality of water and ecosystems' habitats. However, many studies documenting the impacts of nitrogen on urban environs have not properly estimated the contribution of leaky sewer systems—until now. Aging sewer systems are spilling a considerable amount of nitrogen into urban watersheds, diminishing both the quality of water and the ecosystems' habitats. Using water samples from the Pittsburgh-based Nine Mile Run watershed, a Pitt research team reveals ...

New program available to reduce stress among teenagers

2013-03-11

This press release is available in French. Families with a child completing elementary school this year are now preparing their registration for high school, a transition that is often stressful for children. A new program has demonstrated that it is possible to significantly reduce stress in some of these children thanks to a new educational tool designed under the leadership of Sonia Lupien, Director of the Centre for Studies on Human Stress (CSHS) and professor at the University of Montreal. A study published in February in Neuroscience confirms the benefits of ...

Discovery may explain how prion diseases spread between different types of animals

2013-03-11

Medical researchers at the University of Alberta have made a discovery that may explain how prion diseases, like chronic wasting disease and mad cow disease, adapt in order to spread between various types of animals. The research team, led by neurologist Valerie Sim, discovered that a miniscule change in the prions' makeup appears to give the disease the ability to adapt – to mimic and recreate new strains with which it comes into contact. The team has been studying this area for two years. "Prion diseases don't always successfully go from one animal to another, but when ...

Untangling life's origins

2013-03-11

URBANA – Researchers in the Evolutionary Bioinformatics Laboratory at the University of Illinois in collaboration with German scientists have been using bioinformatics techniques to probe the world of proteins for answers to questions about the origins of life. Proteins are formed from chains of amino acids and fold into three-dimensional structures that determine their function. According to crop sciences professor Gustavo Caetano-Anollés, very little is known about the evolutionary drivers for this folding. In collaboration with scientists at the Heidelberg Institute ...

LAST 30 PRESS RELEASES:

Insilico Medicine and Taigen achieves license agreement to develop and commercialize AI-driven PHD inhibitor for anemia of Chronic Kidney Disease (CKD)