What is Graphene Oxide?
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 is considered to be the strongest material in the world, as well as one of the most conductive to electricity and heat. Graphene has endless potential applications, in almost every industry (like electronics, medicine, aviation and much more).
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 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
The latest graphene oxide news:
Researchers report GO-based composite fibers as artificial muscles
Researchers at the University of Pennsylvania have fabricated meter-long composite fibers combining graphene oxide (GO) nanosheets with flexible, conductive polymers that can achieve mechanical strength, toughness, and actuation that surpasses biological muscles.
The team wet-spin a mixture of GO nanosheets and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS) into a composite fiber in which the flexible, conductive polymer is embedded in between aligned, closely-packed nanosheets. The addition of a depleting agent, polyethylene glycol (PEG), improves toughness and elasticity, while chemical reduction of GO to rGO increases electrical conductivity. Finally, the composite fibers are plied with nylon yarns to create a hierarchical composite actuator with capabilities better than typical biological muscles (75 J/kg work capacity and 924 W/kg power density).
Researchers design scalable graphene sensor array for real-time toxins monitoring in flowing water
A team of researchers, led by the University of Wisconsin-Milwaukee, recently developed a path to mass-manufacture high-performance graphene sensors that can detect heavy metals and bacteria in flowing tap water. This advance could bring down the cost of such sensors to just US $1 each, allowing people to test their drinking water for toxins at home.
The sensors have to be extraordinarily sensitive to catch the minute concentrations of toxins that can cause harm. For example, the U.S. Food and Drug Administration states that bottled water must have a lead concentration of no more than 5 parts per billion. Today, detecting parts-per-billion or even parts-per-trillion concentrations of heavy metals, bacteria, and other toxins is only possible by analyzing water samples in the laboratory, says Junhong Chen, a professor of molecular engineering at the University of Chicago and the lead water strategist at Argonne National Laboratory. But his group has developed a sensor with a graphene field-effect transistor (FET) that can detect toxins at those low levels within seconds.
Researchers develop rGO-based approach to address oil-water separation challenges
Researchers from Qatar University (QU), Maimoona Mohamed and Nada Yahya Deyab, along with their supervisor Dr. Shabi Abbas Zaidi, have made progress in addressing the challenge of oil-water separation.
Their research focuses on developing a novel material for efficient oil recovery from oil-water mixtures. By modifying polyurethane (PU) sponges and cotton with reduced graphene oxide (rGO), they have achieved promising results in terms of hydrophobicity, oil-absorption efficacy, reusability, and cost-effectiveness, offering a promising solution to address the issue of water and soil pollution caused by oil spills.
Graphene-Info updates its Graphene Oxide Market Report
Today we published a new edition of our Graphene Oxide Market Report, with all the latest information, including both new research activities. Our market report is a comprehensive guide to graphene oxide (and r-GO) materials and their promising applications in energy storage, composite materials, bio-medical, water treatment and more.
Reading this report, you'll learn all about:
- The difference between graphene oxide and graphene
- Graphene oxide properties
- Possible applications for graphene oxide
- Reduction of graphene oxide to r-GO
The report package also provides:
- A list of prominent GO research activities
- A list of all graphene oxide developers and their products
- Datasheets for over 20 different GO materials
- Free updates for a year
This Graphene Oxide market report provides a great introduction to graphene oxide materials and applications, and covers everything you need to know about GO materials on the market. This is a great guide for anyone interested in applying graphene oxide in their products.
Researchers develop multi-material printer that enables quick and easy 3D printing of flexible devices
Scientists from Nanyang Technological University (NTU), Panasonic Factory Solutions Asia Pacific Pte. Ltd. (Panasonic) and Singapore Centre for 3D Printing (SC3DP) have developed a multi-material printer using multi-wavelength high-power lasers, for quick and easy 3D printing of smart, flexible devices.
The multi-material printer works by utilizing varying wavelengths of laser, creating thermal and chemical reactions capable of transforming common carbon-based materials (polyimide and graphene oxide) into a new type of highly porous graphene. The resulting structure printed with this new graphene is not only light and conductive, but it can also be printed or coated onto flexible substrates like plastics, glass, gold and fabrics, creating flexible devices.
Researchers develop graphene-based wearable textile that can capture energy from body movement to power devices
Researchers from Sichuan University, Chinese Academy of Sciences and Georgia Institute of Technology have developed a graphene-based wearable textile that can convert body movement into useable electricity and even store that energy. The fabric can potentially be used in a wide range of applications, from medical monitoring to assisting athletes and their coaches in tracking their performance, as well as smart displays on clothing.
The accuracy of current wearable electronic devices and various available health monitors remains limited due to the handful of locations on or near the body on which they can be placed, and restricted to a small selection of applications. In the future, if advanced fabrics can be developed, wearable electronic devices integrated into shirts, pants, underwear and hats will be able to track indicators of frailty to assess risk of age-related disease, monitor cortisol levels to track stress levels, or even detect pathogens as part of a global pandemic monitoring network. To take wearable electronics to this next level, monitors will have to be integrated into textiles in a way that is lightweight, unobtrusive and less cumbersome.
Researchers develop GO-based injectable bioelectrodes with tunable degradability
Researchers from Gwangju Institute of Science and Technology (GIST) and Chonnam National University Medical School have developed graphene-based conductive hydrogel electrodes that offer convenience of use, controllable degradation, and excellent signal transmission.
Implantable bioelectrodes are electronic devices that can monitor or stimulate biological activity by transmitting signals to and from living biological systems. Such devices can be fabricated using various materials and techniques. But, because of their intimate contact and interactions with living tissues, selection of the right material for performance and biocompatibility is crucial. Conductible hydrogels are attracting great attention as bioelectrode materials owing to their flexibility, compatibility, and excellent interaction ability. However, the absence of injectability and degradability in conventional conductive hydrogels limits their convenience of use and performance in biological systems. The researchers' new graphene-based conductive hydrogels possess injectability and tunable degradability, furthering the design and development of advanced bioelectrodes.
Researchers use graphene oxide to design a material that can channel mechanical energy in a preferred direction
Researchers from Japan's RIKEN Center for Emergent Matter Science, National Institute for Materials Science (NIMS) and Nagoya University have developed a material, based on graphene oxide nanofillers embedded in a hydrogel, that can channel mechanical energy in one direction but not the other, acting in a “nonreciprocal” way. Using the composite material - which can be constructed at various sizes - the team was able to use vibrational, up-and-down movements, to make liquid droplets rise within a material. Using the material could make it possible to use random vibration usefully to move matter in a preferred direction.
To create the unique material, the group used a hydrogel - a soft material made mainly of water - made of a polyacrylamide network and embedded graphene oxide nanofillers into it, at an angle. The hydrogel is fixed to the floor, so that the top part can move when subjected to a shear force but not the bottom. The fillers are set at an angle, so that they were angled clockwise from top to bottom. When a shear force is applied toward the left, from the direction the nanofillers are leaning, they tend to buckle and hence lose their resistance. But in the other direction, where they are facing away from the force, the applied shear merely makes them stretch even longer, and they maintain their strength. This allows the sheet to deform in one direction but not the other, and in fact the group measured this difference, finding that the material was approximately 60 times as resistant in one direction than the other.
Researchers develop graphene-based cathode in the shape of a thread-like fiber
Researchers at North Carolina State University (NC State), National Science and Technology Development Agency and NSTDA Characterization and Testing Service Center in Thailand have created a graphene-based cathode in the shape of a thread-like fiber. The researchers were then able to use the fiber to create a zinc-ion battery prototype that could power a wrist watch.
Battery prototype with thread-like cathode. Image from NCSU website
The proof-of-concept study is a step forward in the development of a fiber-shaped battery that could ultimately be integrated into garments.
Researchers create graphene hydrogels for efficient water purification
A team of researchers, led by Professor Aravind Vijayaraghavan based in the National Graphene Institute (NGI), have produced 3D particles made of graphene that come in various interesting shapes, using a variation of the vortex ring effect. These particles have also been shown to be exceptionally efficient in adsorbing contaminants from water, thereby purifying it.
Optical and SEM images of donut, spherical and jellyfish morphologies of GO-VR
The researchers have shown that the formation of these graphene particles is governed by a complex interplay between different forces such as viscosity, surface tension, inertia and electrostatics. Prof Vijayaraghavan said: “We have undertaken a systematic study to understand and explain the influence of various parameters and forces involved in the particle formation. Then, by tailoring this process, we have developed very efficient particles for adsorptive purification of contaminants from water”.