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New graphene 'hub' and electronics discovery create excitement in UK

New graphene ‘hub’ and electronics discovery create excitement in UK

Noble laureates Novoselov and Geim, left, along with Nancy Rothwell, president and vice-chancellor of the University of Manchester, meet with UK Science Minister David Willetts and Osborne to discuss plans for a new graphene-based R&D hub to be located at the school. Credit: Univ. of Manchester.

In early October, the United Kingdom’s Chancellor of the Exchequer George Osborne announced plans by the government to invest £50 million (about $80 million) in a new graphene-based R&D center. The center, to be called the Graphene Global Research and Technology Hub, will be located at the University of Manchester.

The location in many ways is a tribute to the past and ongoing work by Andre Geim and Kostya Novoselov, who discovered graphene at the University of Manchester in 2004 and were awarded the 2010 Nobel Prize in Physics. Geim and Novoselov’s pioneering work has allowed them to attract a talented team and stay at the forefront of this field, where there are a lot of ideas for commercialization being brewed.

While no timetables are being proposed in regard to real commercialization opportunities, Osborne, according to a university news release, told attendees of a Conservative Party Conference, “…We will fund a national research program that will take this Nobel-prize winning discovery from the British laboratory to the British factory floor…We’re going to get Britain making things again.”

In the same release, the university, itself, goes on to predict, “The development of the Hub will capitalize on the UK’s international leadership in the field. It will act as a catalyst to spawn new businesses, attract global companies and translate the value of scientific discovery into wealth and job creation for the UK. The center would help develop the technology to allow manufacture on a scale that would open up the promising commercial opportunities, incorporating a large doctoral training center and advanced research equipment.”

To be sure, there are many other graphene research efforts, public and private, in the UK and around the world. Responding to the news about the funding for the Manchester hub, a story at Optics.org notes, “Though it is home to the graphene discoverers, when it comes to future commercialization of the technology the UK will face stiff competition from both competing academic institutions and many of the world’s largest technology companies.”

Already several big-name companies, such as IBM, Hitachi and TDK, have received patents for novel graphene-based devices. But, as is usually the case, having a patent and having a commercial success are unrelated events. While there is a lot of promise, there is still a long way to go in fundamental research and, at the other end of the spectrum, basic processing and application methods.

Given the interest and competition, the £50 million investment could easily be dwarfed if not carefully targeted. Along these lines, the Optics.org story discusses the views of another UK graphene researcher, Karl Coleman (University of Durham), and reports, “Coleman thinks that manufacturing ought to be one of the priority areas for the future technology hub, and also points out that graphene applications go beyond the high-profile areas of electronics, displays and aerospace. ‘[We] would like to see the hub include what we sometimes call the low hanging fruits, such as capacitors, conducting inks and composites, to name just a few, that are likely to be commercialized much sooner,’ he said.”

On the other hand, Geim and Novoselov do have a high-profile electronics application in mind for graphene: the elusive replacement for silicon chip. In a paper, ”Tunable metal-insulator transition in double-layer graphene heterostructures,” recently published in Nature Physics, their group discusses the creation of double boron nitride—graphene sandwich structures. Essentially, they transferred a graphene monolayer on top of a 20-30 nanometer-thick BN crystal (prepared on a silicon wafer). The graphene was then covered with another BN crystal and another graphene monolayer. Both monolayers were given multiterminal shapes, individual electrical contacts and aligned identically over each other.

Ponomarenko with boron nitrate–graphene sandwich device. Credit: Univ. of Manchester.

Ponomarenko with boron nitride–graphene sandwich device. Credit: Univ. of Manchester.

According to the authors of the paper (doi:10.1038/nphys2114), the four-layer structure for the first time allowed the behavior of graphene to be studied in isolation from outside effects.

A separate University of Manchester news release quotes lead author, Leonid Ponomarenko, describing the breakthrough. He says, “Creating the multilayer structure has allowed us to isolate graphene from negative influence of the environment and control graphene’s electronic properties in a way it was impossible before. …So far people have never seen graphene as an insulator unless it has been purposefully damaged, but here high-quality graphene becomes an insulator for the first time.”

Regarding the implications of this work, Geim says in the same release, “Leaving the new physics we report aside, technologically important is our demonstration that graphene encapsulated within BN  offers the best and most advanced platform for future graphene electronics. It solves several nasty issues about graphene’s stability and quality that were hanging for long time as dark clouds over the future road for graphene electronics. …We did this on a small scale but the experience shows that everything with graphene can be scaled up. …It could be only a matter of several months before we have encapsulated graphene transistors with characteristics better than previously demonstrated.”

That sounds like the kind of confidence the UK’s new graphene hub hopes to leverage.

New method for dating ceramic materials

New method for dating ceramic materials

Schematic of rehydoxylation dating method. Credit: Moira

Schematic of rehydoxylation dating method. Credit: Moira

Carbon dating has been used for decades to provide accurate ages of ancient organic materials. Now archeologists have a similar - and fairly simple - technique for accurately dating heat-fired ceramic materials: rehydroxylation dating.

The method exploits the ceramic property of chemically reacting with atmospheric moisture after firing. This reaction causes the material to very slowly gain weight over its lifetime.

A team of members from the Universities of Manchester and Edinburgh discovered rehydroxylation dating and is currently working with the Museum of London. Together, they have been able to date brick samples from a number of historical eras with great accuracy.

The breakthrough actually began in 2003 when the groups discovered a framework for calculating how the rate of reaction between ceramic and water varies over time. They take a small sample of the ceramic and then weigh it with a microbalance. They then heat the sample to 500ºC (thus removing the water). The sample is again monitored with a microbalance to establish the rate at which the ceramic rehydrates. Then, it is a relatively simple matter to calculate the age of the ceramic by extrapolating the information to calculate the time it will take to regain the mass lost on heating

Thus far, they have much success with objects up to 2,000 years old and believe they can extend the technique another 8,000 years.

Tests included a ‘mystery brick.” Archeologists had already knew the age of the brick was between 339 and 344 years. The rehydroxylation method predicted that the brick was 340 years old.

The full research team  was comprised of  Moira Wilson, Margaret Carter, William Hoff, Ceren Ince, Shaun Savage and Bernard McKay from UM, and Chris Hall from UE plus Ian Betts from the Museum, and the team’s findings have been published online by the Proceedings of the Royal Society A.

Wilson noted that their method might be useful if several other applications. One obvious one she mentioned would be to detect forgeries in the archeological world. But she also raised another intriguing application. “The method could also be turned on its head and used to establish the mean temperature of a material over its lifetime, if a precise date of firing were known,” said Wilson. “This could potentially be useful in climate change studies.”

Geim to receive Korber prize for graphene discovery

Geim to receive Korber prize for graphene discovery

Geim

Andre Geim

Andre Geim, who can lay claim to the title of “father of graphene,” is being honored on Friday with the Körber Foundation’s European Science Award for 2009. The award brings a prize of 750,000 euros.

Geim made his discovery of the material at the University of Manchester (U.K.), where he landed after studying physics in Russia and Netherlands, and he is still an active physics professor and researcher at the school.

The annual Körber European Science Award goes to scientist working in Europe for their outstanding scientific achievements and in particular for their future-looking research projects. An international trustee committee chaired by the president of the Max Planck Society, Peter Gruss, selected Geim, who is the 25th winner of the award.