Graphene news and resources

Researchers from the Institute of Photonic Sciences (ICFO) in Barcelona, Spain have developed a highly sensitive photodetector that uses graphene and quantum dots. They say that the new device is a billion times more sensitive to light than previous graphene-based photodetectors because of the quantum dots. A photo-detector such as this can be used in light sensors, solar cells, infrared cameras and biomedical imaging.

Graphene's external quantum efficiency (EQE) is low as it absorbs less than 3% of the light that falls on it. It is also quite difficult to actually extract the electrical current from the graphene. Adding the quantum dots on the graphene sheet helps both of these issues.

Researchers from the University of South Florida and the University of Kentucky managed to create a material the spin of the electrons can be set in a controlled manner. The team suggest using cobalt atoms on a graphene sheet.

The researchers have used state-of-the-art theoretical computations to prove this, they haven't actually made the material and controlled the spin.

Researchers from Europe say they have managed to synthesize silicene - a new Silicon allotrope that forms 2D single-atom sheets. Silicene could rival graphene and can be used to create transistors easily compared to graphene (which has no band gap). The researchers grew the silicene on silver substrates. Some researchers already claimed to have made silicene, but now it is the first time that there is microscopic proof.

In a silicene sheet some atoms are arranged above and below the main "panel" (this is called a buckled honeycomb structure). This creates the band gap and so silicene can be used as an on/off transistor.

Researchers from the UK's University of Exeter discovered a new graphene based material that can be used as an ITO replacement - it's a lightweight, flexible and transparent conductor. In fact it's more flexible than ITO. They call it GraphExeter.

To create the new material, the researchers compressed ferric chloride molecules between two sheets of graphene. They are also working on a spray-on version of the material.

Researchers from the Iowa State University discovered that Graphene behaves like a laser when excited with very short femtosecond light pulses. Graphene has been shown to have two technologically important properties – population inversion of electrons and optical gain. This means that Graphene can be used to make a variety of optoelectronics devices, including broadband optical amplifiers, high-speed modulators, and absorbers for telecommunications and ultra fast lasers.

We already heard of some infra-red graphene related research: Infrared detection using graphene nanoribbons and a graphene-based technology for use in low-cost infrared imaging applications for the US military.

Researchers from the Michigan Technological University discovered that the addition of graphene augmented the conductivity of titanium dioxide, thus increasing the electricity production in a dye-sensitized solar cells by 52.4%. Graphene’s superior electrical conductivity enables it to function as bridges, thus speeding up electron transfer between the titanium dioxide and the photoelectrode.

The team also developed a low-cost, comparatively foolproof technique to synthesize titanium dioxide sheets embedded with the nanomaterial. The idea is to first create a graphite oxide powder and then form a paste by mixing the powder with titanium dioxide. The paste is then applied over a substrate (glass for example) and baked at high temperatures.

The University of Manchester launched a £1M Graphene and innovative materials technology development funding call for a proof-of-principle and feasibility work. They will also be able to supply follow-on funding for successful projects.

This is aimed towards colleagues across the campus who are interested in technology transfer and keen to take the next steps beyond their research results. More details will be issued in September 2012.