Graphene Oxide: Introduction and Market News - Page 38

Researchers from Seoul National University developed a simple method to produce graphene nanonet (GNN) patterns on large areas. The patterns, which contain continuous networks of chemically functionalized graphene nanoribbons, could be used to make biosensor devices. These patterns behave better than GO or GNRs which are commonly used for biological sensing applications and are easy to make.

The GNN structures are made from continuous networks of GNRs with chemical functional groups on their edges. The chemical functional groups in the GNN can be functionalized with biological molecules such as DNA for biochip applications. The researchers successfully performed fluorescence imaging of DNA molecules on the GNN channels and has electrically detected the DNA at 1 nM concentrations using the GNN-based biochip devices.

Researchers from the University of Florida and Hunan Univeristy developed DNA-directed silver nanoparticles (Ag NPs) grown on graphene oxide (GO). These so called Ag@dsDNA@GO composites act as antibacterial agents, decreasing X. perforans (a model plant pathogenic bacterium) cell viability in culture and on plants.

The researchers say that this material exhibit good antibacterial activity due to the synergistic effect between the silver nanoparticles (AgNPs) and the graphene oxide (GO). In a greenhouse experiment they applied this material on tomato transplants and they reported significant reduction of disease caused by bacterial spot compared to the untreated control and the control treated with copper + mancozeb (a standard treatment). The material did not induce any phytotoxic effect on the leaves.

Graphene Laboratories announced that they have successfully managed to convert Lomiko Metal's Quatre Milles property graphite to graphene. They have actually produced graphene oxide (GO) and reduced graphene oxide (RGO) samples. The companies hope that they will be able to create graphene materials on a larger scale and at a reduced price.

In the first step of the conversion process the natural graphite flakes were oxidized and turned into GO by modified Hummer's method. This resulted in a stable aqueous dispersion with concentration of 40 g/L. The GO was then converted into RGO, with a surface area of 500 m² /g and an electrical conductivity 4 S/cm.

Bluestone Global Tech decided to open a new European graphene production plant at the University of Manchester. Bluestone will also partner with the University on several projects. Those projects (detailed below) and the pilot production facility are estimated at £5 million ($7.8 million) which will be funded wholly by BGT.

The National Graphene Center plan

This new deal signs the first strategic partnership of the £61 million National Graphene Institute (NGI) established at Manchester and Bluestone is the first company (except University Spin-Offs Graphene Industries and 2-D Tech) to work at the NGI. Specifically Bluestone will open a pre-production facility and will offer graphene material to the University of Manchester's 100+ scientists and engineers working on graphene and other 2D materials. Later on BGT will setup a larger headquarters and a pilot production line at the NGI and will also work towards partnership with other consumer companies.

Graphenea researchers discovered that adding graphene to ceramic alumina can make it stronger - it is up to 50% less likely to break under strain. Graphenea's method is simple, fast and scalable, and it makes the alumina a hundred million times more conductive to electricity. Graphenea believes the same process will work for other ceramic materials such as silicon carbide, silicon nitride, titania, and zirconia.

A single graphene sheet bridges a crack in alumina

Graphenea's new process starts with graphene oxide - which is mixed with aluminium oxide (alumina) , and then they use a process known as spark plasma sintering (SPS, which drives a large electrical current through the material) to homogenize the graphene/alumina mixture. It was found that adding just 0.22% of graphene to alumina makes it 50% more resistant to the propagation of cracks under strain. Other mechanical properties stayed on par with untouched alumina, while electrical conductivity increased by a factor of a hundred million.

Agar Scientific, a supplier of accessories for microscopy, launched a new range of graphene oxide (GO) support films for TEM. Those new films have been developed in collaboration with the University of Warwick.

Agar says that the new GO film provides a thinner support film of higher mechanical strength, electrical and thermal conductivity compared to support films made from other materials. Agar GO support films are available on holey and lacey carbon and Quantifoil support films.

Researchers from Korea and the Netherlands discovered a new type of ice that forms between graphene oxide layers.

The researchers stacked graphene oxide layers and then passed water through the material (which acts as a membrane) and froze it. This created a single-layer ice. The researchers then used more water and froze it again, which resulted in unique bi-layer ice.

Researchers from the University of Science and Technology of China (USTC) discovered that protein-coated graphene oxide can be used to create efficient anti-bacteria agents. The GO sheets were used as a template to guide silver (or Au@Ag core-shell particles, to be exact) into a 2D array. In this configuration, the silver is much more efficient that with with individual nanoparticles and silver ions.

Mechanical studies showed strong adhesion of the 2D Au@Ag nano-assembly on the cell surface, which cause an aggregation and cellular lysis of the bacteria. The increased local concentration of silver around the bacteria and the "polyvalent" nanoparticle-bacterium interaction were both critical.

Garmor announced a few days ago that it will begin to start producing graphene oxide flakes next month using its low-cost environmentally-friendly production process. Sean Christiansen, Garmor's VP of engineering has been kind enough to answer a few question regarding the company's business and technology.

Dr. Christiansen received his Ph.D. in chemical engineering from the University of California at Santa Barbara in 2001. Since then he worked in several companies, helping them to commercialize new innovations in high technology industries.

Garmor, a new company spun-off from the University of Central Florida (UCF) a couple of months ago to commercialize a new low-cost environmentally-friendly graphene oxide production process, plan to start producing graphene oxide flakes next month (August 2013).

The Garmor facility will have the ability to produce 10 to 20 kg batches of graphene oxide flakes. The yearly capacity will be 100 metric tons. They will offer graphene dispersion in liquid, or dry powder. The company is focused on graphene as an additive for rubbers, plastics or metals - to enhance their strength while lowering the weight.