Graphene joins forces with gold to enable improved neural probes

Apr 20, 2017

Researchers from the Daegu Gyeongbuk Institute of Science & Technology in Korea have used graphene to develop neural probes that are small, flexible and read brain signals clearly.

The probe consists of an electrode, which records the brain signal. The signal travels down an interconnection line to a connector, which transfers the signal to machines measuring and analyzing the signals. The electrode starts with a thin gold base. Attached to the base are tiny zinc oxide nanowires, which are coated in a thin layer of gold, and then a layer of conducting polymer called PEDOT. These combined materials increase the probe's effective surface area, conducting properties, and strength of the electrode, while still maintaining flexibility and compatibility with soft tissue.

MIT team uses graphene as a "copy machine" for semiconductors

Apr 20, 2017

Researchers at MIT have developed a technique that uses graphene as a kind of “copy machine”, to transfer intricate crystalline patterns from an underlying semiconductor wafer to a top layer of identical material.

Graphene as intermediary for semiconductors image

As a great deal of money is spent in the semiconductor industry on wafers that serve as the substrates for microelectronics components, which can be turned into transistors, light-emitting diodes etc., this method may help reduce the cost of wafer technology and enable devices made from more exotic, higher-performing semiconductor materials than conventional silicon.

Non-flammable graphene oxide membrane developed for safe mass production

Apr 19, 2017

Researchers at the University of Arkansas have demonstrated a simple and scalable method for turning graphene oxide into a non-flammable and paper-like graphene membrane that can be used in large-scale production. This tackles the issue of high flammability, which has, according to the team, been an obstacle to further development and commercialization.

Using metal ions with three or more positive charges, the researchers bonded graphene-oxide flakes into a transparent membrane. This new form of material is flexible, nontoxic and mechanically strong, in addition to being non-flammable. Further testing of the material suggested that crosslinking, or bonding, using transition metals and rare-earth metals, caused the graphene oxide to possess new semiconducting, magnetic and optical properties.

Graphene-based transistors show promise for optical technologies

Apr 18, 2017

Researchers at Purdue University, the University of Michigan and Pennsylvania State University have combined graphene with a (comparatively much larger) silicon carbide substrate, creating graphene field-effect transistors which can be activated by light. This may lead to the development of highly sensitive graphene-based optical devices, an advance that could bring applications from imaging and displays to sensors and high-speed communications.

GFETs show promise for optical technologies image

A typical problem of graphene-based photodetectors is that they have only a small area that is sensitive to light, limiting their performance. “In typical graphene-based photodetectors demonstrated so far, the photoresponse only comes from specific locations near graphene over an area much smaller than the device size,” the team said. “However, for many optoelectronic device applications, it is desirable to obtain photoresponse and positional sensitivity over a much larger area”. The researchers tackled exactly this in their new work.

Graphene may assist in producing cells vital for nerve regeneration

Apr 11, 2017

Researchers at Iowa State University (ISU) are developing a graphene-based method to transform stem cells into Schwann-like cells (cells of great importance for various nerve regeneration efforts). If successful, this process has potential to replace the complicated and expensive process used today.

Graphene helps regenerate nerves image

The team's method uses inkjet printers to print multi-layer graphene circuits and also uses lasers to treat and improve the surface structure and conductivity of those circuits. It turns out that mesenchymal stem cells adhere and grow well on the treated circuit’s rough 3D nanostructures. With the addition of small doses of electricity – 100 millivolts for 10 minutes per day over 15 days – the stem cells become Schwann-like cells.