Graphene Oxide: Introduction and Market News - Page 41

Researchers developed a new graphene based film that can detect trace amounts of environmental contaminants. The film is made from semiconductor-graphene-metal, by taking a graphene sheet and depositing metal (silver) nanoparticles and semiconductor titanium dioxide on either side.

The film can be used to test water quality, and this requires precise control over metal deposition and size. The film is capable of selectively splitting hydrogen and oxygen.

Researchers from the University of Wisconsin-Milwaukee developed a new material called Graphene Monoxide (GMO) which is semiconducting. It's also may be easier to scale up compared to Graphene. This new material can provide the key towards graphene based electronics. The researchers say that they discovered GMO by chance...

In their experiments, the team heated Graphene Oxide in a vacuum, to reduce oxygen. But the results surprised them - the the carbon and oxygen atoms in the layers of GO became aligned, transforming themselves into an ordered semiconductor - the GMO.

Researchers from Toyohashi University managed to reduce Graphene-Oxide (GO) to graphene using microorganisms. This is actually a hybrid approach: the chemically-derived GO flakes were reduced to graphene using microorganisms extracted from a river bank near the Tempaku Campus of Toyohashi University.

This may prove a low-cost and highly efficient method to mass produce graphene. It's also environmentally friendly...

Researchers from Northwestern University have developed a new method to oxidize graphene without the collateral damage encountered in the Hummers method commonly used. This process is reversible - which means it offers high tunability, and it outputs a chemically homogeneous graphene oxide.

The idea is to leak Oxygen into an ultra-high vacuum chamber where a hot tungsten filament is heated to 1500 degrees Celsius. This causes the oxygen molecules to dissociate into atomic oxygen which is them uniformly inserted into the graphene lattice.

Northern Graphite signed an agreement with Grafen Chemical Industries to supply +48 mesh and +32 mesh extra large flake graphite for graphene research. The two companies will also collaborate to develop intellectual property rights. Northern will retain a 50% interest in the North American patent rights to any products and processes developed by Grafen.

Grafen developed a novel fabrication method allowing it to synthesize graphene of excellent quality and with considerable yield. Its graphene production process is a highly modified implementation of the conventional graphite oxide manufacturing technique and eliminates known major drawbacks such as extreme disruption of crystal structure of precursor graphite causing low product qualities of electrical conductivity, mechanical performance etc.

A team of researchers led by Professor Sir Andre Geim demonstrated a graphene-Oxide based membrane that is impermeable to all gases and liquids (i.e. it's vacuum-tight) - but water can evaporate though it as if there's no membrane at all.

The researchers explain: "Graphene oxide sheets arrange in such a way that between them there is room for exactly one layer of water molecules. They arrange themselves in one molecule thick sheets of ice which slide along the graphene surface with practically no friction. If another atom or molecule tries the same trick, it finds that graphene capillaries either shrink in low humidity or get clogged with water molecules."

Researchers developed a new blue light emitting hybrid graphene oxide nanosheets. The team used surface functionalization to turn the cyan (491 nm) emitting sheets into 400 nm blue. The team fabricated the new material through the graphene oxide surface functionalization with aryl diazonium salts of 2-aminoanthracene.

The researchers say that these surface-functionalized graphene oxide hybrids has unique optical properties - and they may play an exciting role in opto-electronic devices.

Researchers from China's Zhejiang University in Hangzhou demonstrated meter long graphene fibers - made from nano-sized flakes of graphene oxide. These fibers are strong and flexible and can be tied in knots or woven into conductive "mats".

The researchers use web spinning to turn a graphene oxide solution into long (tens of meters!) fibers. They then treated those fibers with chemical reduction to turn them back in strings of graphene. The next stage for their research is to improve the fiber's strength - which currently cannot compete with carbon fibers.

The following article was sent to us by Corey McCarren and Dr. Elena Polyakova from Graphene Laboratories (a Graphene-Info sponsor), discussing Graphene Oxide and its applications:

Graphene, a multi or single layer sheet of graphite, is considered a key material in producing the next generation of low-cost carbon-based transparent and flexible electronics. Graphene is the strongest material available, as well as being highly transparent, flexible, and the best conductor of heat and electricity. Great effort is devoted to developing an effective yet inexpensive way to produce graphene materials in industrial quantities.

Graphene Supermarket announced that they have expanded their product line and reduced the prices of many current graphene products. They are now offering highly concentrated graphene oxide at the lowest price per gram. The company also added two high-surface area materials, Reduced Graphene Oxide and ultrafine Graphene Nanoplatelets.

Graphene Supermarket is operated by Graphene Laboratories and is a sponsor of Graphene-Info.