What is graphene?

Graphene is a material made of carbon atoms that are bonded together in a repeating pattern of hexagons. Graphene is so thin that it is considered two dimensional. Graphene's flat honeycomb pattern gives it many extraordinary characteristics, such as being the strongest material in the world, as well as one of the lightest, most conductive and transparent. Graphene has endless potential applications, in almost every industry (like electronics, medicine, aviation and much more).

An ideal graphene sheet image

The single layers of carbon atoms provide the basis for many other materials. Graphite, like the substance found in pencil lead, is formed by stacked graphene. Carbon nanotubes are made of rolled graphene and are used in many emerging applications from sports gear to biomedicine.

What is graphene oxide?

As graphene is expensive and relatively hard to produce, great efforts are made to find effective yet inexpensive ways to make and use graphene derivatives or related materials. Graphene oxide (GO) is one of those materials - it is a single-atomic layered material, made by the powerful oxidation of graphite, which is cheap and abundant. Graphene oxide is an oxidized form of graphene, laced with oxygen-containing groups. It is considered easy to process since it is dispersible in water (and other solvents), and it can even be used to make graphene. Graphene oxide is not a good conductor, but processes exist to augment its properties. It is commonly sold in powder form, dispersed, or as a coating on substrates.

Graphene Oxide structure

Graphene oxide is synthesized using four basic methods: Staudenmaier, Hofmann, Brodie and Hummers. Many variations of these methods exist, with improvements constantly being explored to achieve better results and cheaper processes. The effectiveness of an oxidation process is often evaluated by the carbon/oxygen ratios of the graphene oxide.

Graphene oxide uses

Graphene Oxide films can be deposited on essentially any substrate, and later converted into a conductor. This is why GO is especially fit for use in the production of transparent conductive films, like the ones used for flexible electronics, solar cells, chemical sensors and more. GO is even studied as a tin-oxide (ITO) replacement in batteries and touch screens.

Graphene Oxide has a high surface area, and so it can be fit for use as electrode material for batteries, capacitors and solar cells. Graphene Oxide is cheaper and easier to manufacture than graphene, and so may enter mass production and use sooner.

GO can easily be mixed with different polymers and other materials, and enhance properties of composite materials like tensile strength, elasticity, conductivity and more. In solid form, Graphene Oxide flakes attach one to another to form thin and stable flat structures that can be folded, wrinkled, and stretched. Such Graphene Oxide structures can be used for applications like hydrogen storage, ion conductors and nanofiltration membranes.

Graphene oxide is fluorescent, which makes it especially appropriate for various medical applications. bio-sensing and disease detection, drug-carriers and antibacterial materials are just some of the possibilities GO holds for the biomedical field.

Buy Graphene Oxide

Graphene oxide is relatively affordable and easy to find, with many companies that sell it. It does, however, get confusing since different companies offer products that vary in quality, price, form and more - making the choice of a specific product challenging. If you are interested in buying GO, contact Graphene-Info for advisement on the right GO for your exact needs!

Further reading

Latest Graphene Batteries news

Spray-on graphene-based coating for improved desalination membranes

Sep 13, 2017

An international group of researchers, including scientists from Shinshu University in Japan and Penn State’s ATOMIC Center, created a graphene and graphene oxide-based coating for desalination membranes which are said to be more scalable and sturdier than current nanofiltration membrane technologies available.

The result of this creation would hopefully be a filter for clean water solutions, protein separation, wastewater treatment, as well as pharmaceutical and food industry applications. This membrane uses a simple spray-on technology to coat a mixture of graphene oxide and graphene in solution onto a backbone support membrane of polysulfone that is modified with polyvinyl alcohol. The team reports that even in the early stages of the development of the membrane, it can already reject 85% of salt, which is sufficient for agricultural purposes, and 96% of dye molecules.

Ionic Industries announces a process for economically mass-producing graphene micro supercapacitors

Sep 11, 2017

Ionic Industries recently announced a process for economically mass-producing graphene micro supercapacitors and added that its directors and key personnel have taken direct stakes in the company.

Ionic Industries' graphene supercapacitors patent image

Ionic stated that since it published the positive results on its graphene micro planar supercapacitors 2 years before, the company has been working toward developing a device that not only demonstrates similar performance but can be produced at scale to deliver an economically viable device.

The Graphene Catalog - find your graphene material here

NSF grant to fund development of inkjet-printed graphene-based water quality sensors

Sep 04, 2017

The National Science Foundation recently awarded University of Wisconsin-Milwaukee scientists $1.5 million to perfect a method of mass-producing graphene-based small water sensors using inkjet printing. The goal is to determine whether the process can be customized in order to scale up production and in a more economic way than traditional manufacturing methods.

Inkjet-printed graphene-based water quality sensors image

The graphene-based sensors, developed at UWM, reportedly outperform current technologies in accuracy, sensitivity and sensing speed. Their performance and size make them useful for continuously monitoring drinking water for miniscule traces of contaminants like lead.

Manchester U team prints flexible GO-based supercapacitors on fabrics

Aug 14, 2017

Researchers from The University of Manchester recently demonstrated flexible graphene-based supercapacitors printed directly on to textiles using a simple screen-printing technique.

Manchester U prints GO-supercapacitors on fabrics image

The solid-state flexible supercapacitor device has been demonstrated by using conductive graphene-oxide ink to print onto cotton fabric. The printed electrodes reportedly exhibited excellent mechanical stability due to the strong interaction between the ink and textile substrate.

Masdar team reports progress of graphene-based membranes for water desalination project

Aug 06, 2017

Researchers at the UAE-based Masdar Institute, part of the Khalifa University of Science and Technology, have announced significant progress in their research in the field of optimized graphene-based membranes, which aim to make water filtration and desalination more efficient and sustainable.

The team worked to develop membranes made of layered reduced graphene-oxide sheets that are able to block the passage of salt ions in a membrane-based seawater desalination process. The spacing between the sheets is what ultimately affects the membrane’s efficacy, or its ability to filter impurities like salt ions while still permitting water molecules to pass through. The spaces between sheets must be just right – if they are too large and salt ions are not filtered out, and if they too small and even water molecules are unable to penetrate the membrane.