What is a coating?
A coating is a covering that is applied to the surface of an object. The purpose of applying the coating may be decorative, functional, or both. Coatings are ubiquitous and can be found on walls, furniture, on all sorts of wires and printed circuits, the outside of houses and cars, and much more. In addition, the decorative duties of coatings span quite a broad spectrum.
Decorative coatings are mainly used for their color, texture or other visual property. Functional coatings are applied to change the surface properties of the substrate, such as adhesion, wettability, corrosion resistance, wear resistance and more. In some cases, the coating adds an entirely new property such as a magnetic response or electrical conductivity and forms an essential part of the finished product.
Coatings may be used in various processes, that are roughly divided into: vapor deposition, spraying, chemical and electrochemical techniques, roll-to-roll coating processes and other, less prominent techniques.
What is graphene?
Graphene is a two dimensional layer of carbon atoms, arranged in the form of a honeycomb lattice. It is touted as a “miracle material” because it is endowed with an abundance of astonishing traits - this thin, one atom thick substance is the lightest, strongest, thinnest material known to man, as well as the best heat and electricity conductor ever discovered - and the list does not end there. Graphene is the subject of relentless research and is thought to be able to revolutionize whole industries, as researchers work on many different kinds of graphene-based materials - each one with unique qualities and purpose.
Graphene for coatings
The vast selection of extraordinary properties that graphene possesses can open the door to many interesting types of coatings, paints, inks and more. Graphene's high resistivity can make for durable coatings that do not crack and are resistant to water and oil; its excellent electrical and thermal conductivity can be used to make various conductive paints, and a strong barrier effect can contribute to extraordinary anti-oxidant, scratch-resistant and anti-UVA coatings.
Graphene enables a wide array of functional coatings and paints, for many possible applications. Among these can be high performance adhesives enabled by graphene's high adhesion property, anti-bacterial coatings, solar paints (capable of absorbing solar energy and transmitting it), paints that provide isolation for houses, anti-rust coatings, anti-fog paints and UV ray blockers, non-stick coatings for various domestic applications (like frying pans and countertops) and even a much-hyped possibility (currently under scientific examination) of a coating that turns a regular wall into a screen.
Graphene-enhanced products are yet to reach widespread commercialization. Nonetheless, given graphene’s impressive array of properties and the vigorous R&D that is taking place, graphene-enhanced coatings should not be too far away.
The Sixth Element Materials, a Chinese company that focuses on R&D, mass production and sales of graphene and related materials, showcased its graphene-zinc anti-corrosion primer used for offshore wind power tower, that can come at a competitive price compared with zinc rich epoxy primer.
Garmor, the University of Central Florida spin-off formed to develop a new graphene oxide flakes production process, has developed graphene oxide-based coatings useful for limiting UV radiation damage to sensors and polymers. Garmor's transparent GO-films are reportedly derived from a commercially-viable and scalable process that can be readily implemented with minimal constraints.
The Spain-based Graphenano announced the launch of a graphene-based series of paints and coatings called Graphenstone in 2014. These are said to be very strong and also acts as a protective layer against environmental damage. Graphenstone is made from a graphene powder and limestone powder.
The British Electro Conductive Products released a sprayable transparent conductive coating based on a CNT and graphene platelets (GNP) hybrid material. TBA are targeting the food, electronics, pharmaceuticals and petrochemicals markets.The new ATEX-compliant product is available as a clear, anti-static aerosol, and it should also be available as bulk paint. Its application will safeguard electronic equipment used in explosive environments and bring it up to European standards.
The latest graphene coating news:
Researchers at Northwestern University and Clemson University in the U.S, along with researchers from Sejong University in Korea, have examined the origins of degradation in high energy density LIB cathode materials and developed graphene-based strategies for mitigating those degradation mechanisms and improving LIB performance.
Their research could be valuable for many emerging applications, particularly electric vehicles and grid-level energy storage for renewable energy sources, such as wind and solar.
ZEN Graphene Solutions has announced that it has signed a binding letter of intent (LOI) with Trebor Rx Corp. (Trebor), a Canadian personal protective equipment mask manufacturer with an initial production facility.
This LOI includes the initial purchase of ZEN’s patent pending graphene-based viricidal coating for a minimum of 100 million masks/filters. This initial minimum order is for the first year and is subject to Health Canada approvals.
First Graphene (FGR) has announced that it has agreed with TPR2 and its Australian distributor Exfire to work on the commercialization of a fire retardant coating utilizing FGR’s PureGRAPH.
First Graphene holds the global licensing rights to a graphene-based fire-retardant coating from the University of Adelaide (UoA). Development of the FireStop product has been conducted over a three-year period in collaboration with the UoA, as part of the Company’s participation as a Tier-1 member of the ARC Research Hub for Graphene Enabled Industry Transformation. Patents have progressed to National Phase and are in the examination phase in Australia, Europe and the United States of America.
Researchers at Los Alamos National Laboratory have found a possible way to evaluate the effectiveness of graphene-based protective barriers.
“It’s about creating and using extra-corrosive air and observing its accelerated effect on the graphene-protected materials. Simply by imparting oxygen gas molecules with a slight kinetic energy, we could extract information about decades-worth of corrosion in a minute,” said Hisato Yamaguchi, a lead Los Alamos National Laboratory scientist for this research. “We create a portion of air artificially, including oxygen with a physics-defined energy distribution, and expose that to graphene-protected metals.”
G2O Water Technologies (G2O) has announced an expansion into a new laboratory at Liverpool City Region’s Sci-Tech Daresbury following a £600,000 investment, including £320,000 of funding from NPIF – Maven Equity Finance, managed by Maven and part of the Northern Powerhouse Investment Fund.
Headquartered in Manchester, the G2O uses graphene-based coatings technology to provide high quality and cost-effective solutions to a broad range of filtration applications. G2O’s technology is used for the treatment of water waste across multiple markets, including oil, gas and industrial.