Researchers at the University of Virginia (UVA) have devised a process for converting retired Li-ion battery anodes to graphene and graphene oxide (GO). A paper on the work is published in the ACS journal Nano Letters.
Schematic illustration of the proposed smart fabrication of graphene and graphene oxide from end-of-life batteries. Zhang et al.
… accompanying the booming expansion of the Li-ion battery market, a tremendous amount of batteries retire every year and most of them are disposed of in landfills, which not only causes severe waste of precious sources but also induces hazardous soil contamination due to the plastic components and toxic electrolytes. So far, only 1% of end-of-life Li-ion batteries have been recycled. Apparently, it is an urgent necessity to develop effective battery recycling techniques.
… A rational strategy to simultaneously solve the environmental issues from waste batteries and graphite mining is to fabricate graphene directly from end-of-life battery anodes.
… Here, graphite powders from end-of-life Li-ion battery anodes were used to fabricate graphene.
—Zhang et al.
Graphite powders collected from end-of-life Li-ion batteries exhibited irregular expansion because of the lithium-ion intercalation and deintercalation in the anode graphite during battery charge/discharge.
Such lattice expansion of graphite can be considered as a prefabrication of graphene because it weakened the van der Waals bonds and facilitated the exfoliation.
—Zhang et al.
This “prefabrication” process facilitates both chemical and physical exfoliations of the graphite. Comparing with the graphene oxide derived from pristine, untreated graphite, the graphene oxide from anode graphite exhibited excellent homogeneity and electrochemical properties.
The lithiation aided pre-expansion enabled 4 times enhancement of graphene productivity by shear mixing, the researchers found.
The graphene fabrication was seamlessly inserted into the currently used battery recycling streamline in which acid treatment was found to further swell the graphite lattice, pushing up the graphene productivity to 83.7% (10 times higher than that of pristine graphite powders).
When we first spoke to William Blythe back in 2016, we were trying to get a handle on how a 170-year-old specialty chemical company found itself involved as a major graphene producer. Now nearly two years later we got to visit with the company again to see what’s changed from since we last spoke.
For those of you who would like more regular updates on what William Blythe is doing and thinking about when it comes graphene, you can visit their blog. And while there you can order some material on thesame site.
Q: When we spoke to you 18 months ago, William Blythe expected to boost graphene oxide production to the tonnage scale within the next 6-12 months from a lab production level of around 20Kg. Has that production capacity increase happened?
A: William Blythe has definitely seen an increase in demand for graphene oxide since we last spoke. We have been working on scale up of all three of our graphene oxide products, with significant investments made and planned to ensure we always stay ahead of our customers’ needs. As application development has been slower than originally predicted by our customers, we have been able to scale to an interim production capacity of about 200 kg pa.
Q: At the time we spoke last, William Blythe was investing heavily in R&D, focusing on innovation and product development. How has that program developed over the last 18 months?
A: William Blythe has continued building its R&D program and has added several projects since we last spoke. One significant area of investment is in the energy storage sector, with a commitment to spend £1m over the next 3 years in energy storage research. One of these projects is in collaboration with the National Graphene Institute at the University of Manchester and aims to develop novel anode materials. As a company, we are very committed to developing the materials needed to enable the exciting technologies needed for the future.
Q: Can you also address along these lines how your supply line has developed, i.e. what are the expectations of your customers in terms of batch-to-batch consistency?
A: William Blythe’s customers, across our whole product range, always require the highest level of batch-to-batch consistency. Our products are generally used in demanding applications, where the performance of the product could be hugely affected by small variations in either the chemical or physical properties of the materials we supply. We pride ourselves on offering consistently high-quality products. Both the quality and batch-to-batch consistency of our graphene oxide has been commended by several customers.
Q: Are you still supplying strictly graphene oxide or have you branched out to other graphene products, such as single-crystal monolayer graphene? Why have you chosen one product approach, or the other?
A: As we discussed previously, William Blythe is an inorganic specialty chemicals manufacturer. The chemical exfoliation route we use to synthesize our graphene oxide is very well aligned with our core capabilities, which means we are very well positioned to scale the process effectively and successfully.
Q: We discussed ad hoc industry standards for graphene last time we spoke. Have those become more formalized? And what is the state of graphene standardization across producers?
A: A lot of work is taking place on standardization of graphene materials, however the early standards are more focused on graphene as opposed to graphene oxide. While standards are now being written and the first standards are now published, there is still a need to get the wider market on board as terminology is not always being fully understood and adopted by those in the graphene community.
Q: A year-and-half ago, William Blythe expressed confidence that graphene "will be well established in the supply chain of several industries within the next 5 – 10 years”. Has anything occurred since that then enforces that belief, or perhaps you have become more cautious?
A: Based on the work we know of in this market, the forecast of graphene oxide being well established in some industries by 2026 is very realistic. William Blythe is, as you know, working on increasing production capacity of their graphene oxide to meet customer demands over the coming years. While some applications are commercializing right now, William Blythe is also working on several longer-term projects, we expect these applications to take several years to commercialize, but would still anticipate commercial volume demand in these areas before 2026.
Last week, the city of Luxembourg played host to The Economist’s “The Future of Materials Summit”. The agenda was heavily influenced by the Russian-based single-wall carbon nanotube (SWNTs) producer, OCSiAl, which not only sponsored the event but also plans to open a SWNT production facility in Luxembourg.
With the Luxembourg prime minister, Xavier Bettel, providing a keynote in which he expressed his hope that Luxembourg could bring back its manufacturing glory days when it was one of Europe’s largest steel producers, the hope seemed to be squarely placed on the potential of SWNTs to be the engine for Luxembourg’s economic transformation back to manufacturing.
In what may have been the most interesting set of ironies of the conference, one of the world’s largest steel producers today—Tata Steel—provided testimony that the future of steel manufacturing is not turning towards the expensive and finicky SWNTs, but instead is developing a cheaply produced form of graphene that promises to drastically improve corrosion resistance in steel.
Sanjay Chandra, Chief of Research and Development and Scientific Services at Tata Steel, provided one of the only examples at the conference on how novel materials move from discovery to high volume production. And in this case, the discovery process was quite unexpected.
“We were looking at coatings that would improve the corrosion resistance of steel,” said Chandra in an interview immediately after his presentation. “There is already zinc, of course, but there are a lot of environmental issues with the zinc as well as the costs associated with it. So we came across this bio product from a tree. It is the secretion that an insect makes as it sits on the seeds of the tree. You could call it a bio extract, and we were able to convert this material into graphene.”
The graphene takes the form of graphene oxide in which the carbon-to-oxygen ratio is about 30% to 40%, and, according to Chandra, it provides very good corrosion resistance.
“Its conductivity is good enough for some of the sensors that are used in the pharmaceutical industry and the main feature of our product is that can we can produce it at a very low cost because it can be produced in very large volumes and very rapidly,” said Chandra.
Currently, the process that Chandra and his colleagues at Tata Steel are employing with the graphene oxide is a manual process of dipping the steel in a liquid created by this powder. While this is good enough for testing, Chandra concedes that in order to replace zinc in steel production they will need to develop a more refined process.
“We need a process that can fit into a steel plant that is producing these galvanized sheets of steel at very high speeds and all in one sequence,” he added. “So for us to be able to do that that's a bit of a challenge.”
Part of the challenge is that it is very difficult to get someone to retrofit a steel assembly line because of production disruptions. However, with the graphene material offering at least a doubling of corrosion resistance over zinc and offering biocompatibility there is certainly reason to look into overcoming these production obstacles.
Most of the research and development that has been done so far with the material and processes has been performed in house at Tata Steel. Chandra explained that this was not because of any reticence to work with outside research groups—which Tata Steel does quite regularly—but instead they have not been able to identify the appropriate group that could help them scale up the production for steel applications. Another problem is just the culture of the steel industry, which has proven to be not very good at engineering and design, which is where the current problems resides.
To address these issues Tata Steel has taken the forward thinking measure of funding a new research group at the Indian Institute of Technology in Madras to look at among other things this material and how to potentially scale up production. Tata steel has also enlisted the research support of The Centre for Nano Science and Engineering (CeNSE) in Bangalore, India to investigate the potential sensor applications of the graphene material.
For Chandra the project has been ongoing for the last two-and-a-half years, and he says the development that has been made thus far has been very fast. “We’ve gone from a research curiosity and then to a research project in R&D to where we are now with a small production unit on the R&D level,” he added.
In addition, Chandra believes that the work at CeNSE could start producing tangible dividends from their research in as soon as a year from now. The material could enable glass to turn from clear to opaque with just the passing of current through it with the graphene providing the conductivity in the glass.
In the meantime, Chandra is looking for other collaborators, especially any organizations that can offer expertise and insight on how to scale up a steel production process that employs a graphene oxide for corrosion resistance.
In that interview, Yu said the first approach of the three is to use graphene in the creation of functional coatings. The second approach involves producing lamellar structures with nano-channels, which requires using fine layers of alternating types of materials. G2O Water is doing a bit of both of these approaches by creating a functional coating that can be applied to today’s polymer water membranes, and also creating scalable fabrication of lamellar structures of graphene oxide.
All of these approaches to using graphene in water applications is taking on increased interest after news came out last week that researchers from the University of Manchester have developed a graphene oxide membrane that in addition to filtering out small particles has small enough pores that it can filter out salt ions. This approach, which was published in the journal Nature Nanotechnology, falls into the approach taken by the MIT researchers.
The Manchester researchers have managed to overcome a key problem in this approach when the membranes swell up after being immersed in water for some time, allowing smaller particles to continue to pass through.
“Realization of scalable membranes with uniform pore size down to atomic scale is a significant step forward and will open new possibilities for improving the efficiency of desalination technology,” said Rahul Nair, a professor at the University of Manchester and one of the co-authors of the research, in a press release. “This is the first clear-cut experiment in this regime. We also demonstrate that there are realistic possibilities to scale up the described approach and mass produce graphene-based membranes with required sieve sizes.”
Of course, the imprimatur of the University of Manchester on anything to do with graphene suddenly makes this latest research noteworthy. However, the final arbiter on whether this graphene approach or the others like it for either desalinating or purifying water remains squarely on the industry.
While the mainstream press--like the BBC--has seemingly ignored all other efforts for using graphene in the desalination or purification of water--setting up the Manchester research as a kind of first in the field--the trade press has been a bit more circumspect.
The publication Water & Wastewater International (WWi) has a pretty thorough assessment of the latest Manchester research and how it stacks up to other efforts for desalinating water using graphene.
While WWi remains pretty sanguine about the general prospects of using graphene for water desalination, they get some expert opinions that characterizes this latest research as something of a long shot at this point.
Graeme Pearce, principal at Membrane Consultancy Associates (MCA) told WWi in an interview: "The development at the University of Manchester aims to produce a membrane with a highly controlled character, free from defects. Given the materials used, longevity should also be good. The challenge will be whether the membrane can be effectively used with the current form factor (the spiral wound element mounted in series in long pressure vessels) and using current process design concepts.
"Alternatively, the membrane might be better exploited by a completely different approach to process design, which would be high risk and slow to introduce, but might have a much greater long term impact if the improved membrane can be exploited more efficiently."
He added: "The key issue would be to demonstrate both performance and longevity in the first instance and then establish what features of the current approach to desalination plants limit the benefits of a new membrane and what can be done to remove these impediments."
It turns out that the technology of G2O Water technologies might have the inside track at this point, according to Pearce.
He added: "This preserves the form factor and should be more easily adopted by the industry. The development is still early stage and the longevity of the coating has yet to be established, but the approach appears to be promising and initial results on performance enhancement have been encouraging. This is more likely to allow a radical optimization of existing practice rather than the potentially more revolutionary but higher risk development from Manchester."
When we think of graphene, we conjure up cutting-edge and emerging technologies that have a place in a sci-fi movie, and rightly so. But to make those dreams into reality it is coming down to a nearly two-century-old specialty chemical company to produce the building blocks. William Blythe, a 170-year-old inorganic specialty chemical and advanced materials company based in the UK, has established itself as one of the premier graphene oxide producers, enabling other companies to fabricate next-generation devices.
In May of this year, William Blythe added graphene oxide to its portfolio of products and ramped up production of the material to large lab-scale manufacturing, reaching kilogram capacity production. At this point, the company can manufacture up to 20 kg of powdered graphene oxide per annum with the aim of increasing to tonnage scale in the next 6 – 12 months.
To accompany the launch of this new product line, William Blythe has created its GOgraphene website at which you can order the company’s graphene oxide product, as well as find a blog that discusses the experience of launching a graphene-based business.
The Graphene Council took the opportunity of this recent business launch to talk to William Blythe’s Global Marketing & Sales Director, Marc C.G. de Pater, and in the interview below you can read how this company evolved and found itself at the forefront ofone of the most cutting-edge materials, graphene.
Q: Can you explain how a 170-year-old specialty chemical company like William Blythe found itself transitioning into the production of graphene oxide?
A: William Blythe was originally founded to support the textile industry, however over the last 170 years, William Blythe has transformed into an inorganic chemicals manufacturer, who is now on its way to becoming an advanced materials supplier. The expertise William Blythe has developed over the years, as well as its focus on innovation and product development, means the chemistry of graphene oxide fits very well with William Blythe core capabilities.
Q: Can you explain a little bit about the graphene oxide dispersions you produce and how these dispersions fit into the value chain that ultimately lead to products that may find their way into our store shelves?
A: William Blythe currently manufactures a high concentration graphene oxide dispersion at 10 mg/mL, or 1%. The manufacture of a high concentration is designed to maximize the options for graphene oxide users – the optimal concentration of graphene oxide is still being researched but is likely to be highly dependent on the application in question. Higher graphene oxide concentrations can lead to difficulty when diluting the dispersion, however William Blythe has developed a dispersion which can be very easily diluted, as demonstrated in this video: https://www.youtube.com/watch?v=xLixtvZRq0w.
In terms of the value chain, the nature of graphene oxide means William Blythe is positioned at the start. The graphene oxide dispersions offered allow William Blythe’s customers an opportunity to revolutionize the products they sell. Any graphene oxide, or graphene oxide derivative, that ends up on the store shelves is likely to be present in small concentrations, with consumers only aware of its presence through the enhanced properties they observe in the products they purchase.
Q: Why has your company struck upon graphene oxide production rather than single-crystal monolayer graphene? Was that because of what your customers were looking for or did it fit your business plans better in terms of both current production and how you see the market developing?
A: A combination of both – while the chemistry of graphene oxide synthesis fits very well with William Blythe expertise, there is also a strong argument for graphene oxide use over graphene in many situations. Graphene is a hydrophobic material, which means it can be very difficult to obtain good dispersions in various media. Graphene oxide, however, is highly hydrophilic and is reported to disperse very well in many polar solvents. By obtaining the required dispersion with graphene oxide and then reducing to graphene, graphene oxide may also allow users to gain the desired properties of graphene while achieving the dispersion characteristics needed.William Blythe therefore believes graphene oxide has the ability to exist in the graphene market, employed in systems and applications where graphene would not be suitable.
Q: There seems to be an issue of wide disparity in the quality of graphene products. Is this something that will just be sorted out in the marketplace, or do you think standards will need to be instituted before this problem is fully addressed?
A: Graphene products are so new to the market it is understandable that there is so much variation in product quality. As more users investigate and adopt graphene or graphene oxide products into their applications, a consensus is likely to evolve naturally over what constitutes appropriate material for use. Formal standards may come into place at some point, however if graphene derivatives are already well established by this time it would be reasonable to expect these to take the approximate form of the informal standards already adopted. William Blythe will of course support the establishment of both informal and formal standards for graphene oxide where possible.
Q: What is the range of applications that your customers are using for the graphene oxide that you produce? And what is it about your product that makes them choose yours rather than others, i.e. price, quality, etc.?
A: William Blythe’s graphene oxide is of interest to a wide variety of applications. While it is not possible to disclose specific applications or customers, we can indicate that the range is broad enough to cover applications from membrane technology to advanced coating technology. The biggest attractions to William Blythe’s graphene oxide are its quality (dispersibility and number of layers) and the scale at which the material can be supplied. As a long established chemical manufacturer William Blythe is already planning to scale up manufacture to tonnage quantities. This, combined with a long history of manufacturing and supplying high quality chemicals gives customers confidence in William Blythe’s ability to support the launch of their technologies.
To support those still in research phases of graphene oxide application development, William Blythe recently launched a webshop, www.go-graphene.com , which sells research quantities of graphene oxide powder and aqueous dispersions. The feedback from this indicates the biggest draws are the competitive pricing and excellent dispersion characteristics.
Q: You are located near the University of Manchester where graphene was first discovered and a major research facility has been created. Has this proximity had an impact on your business? If so, in what way?
A: To an extent, the proximity of William Blythe’s headquarters to the University of Manchester has been of benefit. Members of both the commercial and technical teams at William Blythe have been able to attend meetings and conferences which may have been more difficult if the locations had been less convenient. These events have helped William Blythe to establish some of the understanding and network which are invaluable to the business today. Having said that, William Blythe is sufficiently committed to the development, manufacture and commercialization of graphene oxide that the same activities would have been pursued irrelevant of geography.
Q: Do you foresee William Blythe moving further up stream in the value chain by manufacturing products that employ your graphene oxide? Or will you remain producing dispersions of graphene oxides?
A: William Blythe intends to continue selling both graphene oxide dispersions and powders as well as any other relevant graphene derivatives which make sense in the future. Alongside these it is possible that William Blythe will offer products which fit in further down the supply chain. The volume and caliber of global graphene oxide research is so high at the moment it seems very likely there are other opportunities for William Blythe in the graphene derivative marketplace.
Q: Can you paint a picture of both William Blythe’s graphene business in the next 5 to 10 years and how the market will look more generally in those time periods?
A: Based on William Blythe’s market intelligence, it is anticipated that graphene products will be well established in the supply chain of several industries within the next 5 – 10 years. Naturally this means graphene oxide volume requirements will have risen and potentially the market price will be lowered. William Blythe expects to still be offering highly competitive pricing for high quality graphene oxide, with manufacture moving to a new dedicated graphene oxide plant. Early estimations predict William Blythe’s graphene oxide plant will have an annual production capacity of 10 tonnes.