May 2012

Researchers from the University of Florida have managed to develop the most efficient graphene based solar cell to date. This was achieved by doping it with an organic material, and it increases the efficiency by more than four times (from 1.9% to 8.6%).

The researchers used a cheap and environmentally stable organic coating layer to reduce the graphene electrical resistance by adjusting the Fermi level. In the new solar cells, a single layer of graphene placed on top of a silicon wafer serves as a Schottky junction, the main component of simple photovoltaic devices called Schottky junction solar cells.

Researchers from the University at Buffalo developed a new graphene-based anti-corrosion coatings. These new coatings are effective and eco-friendly - as opposed to currently used hexavalent chromium (which is a potential carcinogen) based coating.

Graphene's conductive and hydrophobic properties are helpful in preventing corrosion by repelling water and inhibiting electro-chemical reactions. The graphene-based composite can be fine-tuned for use in factories specializing in chrome electroplating.

Researchers from Samsung's Advanced Institute of Technology have developed a new graphene-silicon Schottky barrier that enables graphene to switch electric current on and off. The researchers explored potential logic device applications based on this technology.

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.