What is Graphene?

For an undergraduate scientist, the answer to the question “What is graphene?” is perhaps all ironed out. This material, one million times thinner than paper and the ‘strongest material known to man’, is an allotrope of carbon, made up of a single layer of carbon atoms arranged in a hexagonal lattice.

But whilst that’s one (strict, technical) definition of ‘true’ graphene, in reality the term is used liberally to describe a plethora of different materials. ‘Graphene’ has transformed into an umbrella term to describe a family of graphene-like materials which can differ in formation method, size, shape, type and nature of defects, and purity (to name just a few).

Importantly, not all practical applications of ‘graphene’ necessarily require pristine, monolayer, graphene and, as the number of new applications for these ‘wonder’ materials increase, and as many producers race to meet demand, a common understanding of what ‘graphene’ means, exactly, is essential to avoiding ambiguity. 

The drive towards standardisation

It may seem a distraction to exciting technical progress, but the process of standardisation in fact enables commercialisation, scale-up and further innovation. For example:

  • With robust standardisation comes increased trust in the suppliers of graphene who follow those standards, allowing suppliers to differentiate themselves from competitors in the market.

  • A buyer looking to scale up their graphene-enabled technology can gain supply chain confidence, and know that if Supplier A fails, Supplier B can provide them with the same product. In the ideal case, simple comparison of technical data sheets, rather than trial and error testing of multiple suppliers, makes this process efficient and gives the buyer confidence.

  • Standardisation is key to guiding and achieving legal regulation, too. Recognition of these materials by regulatory bodies such as REACH, and gaining a full understanding of the impact of these materials on the environment and human health, expands the potential markets for these materials. 

  • The process of standardisation can encourage innovation. When buyers have confidence in the product they can perform detailed investigation into how changes in their product affect performance, or into new product areas. As the differentiation between members of ‘family graphene’ becomes more refined, so do, potentially, the applications for these materials. The very process of standardisation itself, engaging multiple stakeholders, promotes communication, new ideas and collaboration. 

How is it being achieved?

The National Physical Laboratory (NPL), in partnership with the University of Manchester and in collaboration with producers such as First Graphene Ltd., has been working towards this goal, with a real-world, commercial outlook.

The process of standardisation is by no means trivial, with the need to balance what is theoretically achievable with what is really required in the market, and allowing these standards to enhance and enable, rather than stifle, growth. Developing rigorous standards with multiple stakeholders (more than 30 countries sit on the technical committee for nanotechnologies) takes a long time; developing each ISO standard can take between 2 and 5 years. 

The initial focus of the NPL has been on what measurements to perform, and how to perform those measurements to the highest level of accuracy and precision.

These ISO standards set the definitive methods by which graphene, bilayer graphene, and graphene nanoplatelets, synthesised from powders or dispersions and by chemical vapour deposition, can be characterised, measuring properties such as the number of layers, the lateral flake size, the level of disorder, layer alignment and specific surface area. An ongoing process of verification of those standards, orchestrated by the Versailles Project on Advanced Materials and Standards (VAMAS), takes place in labs worldwide. The standards are by no means static and respond to improvements in technology that allow the uncertainty to be reduced further, and for improved differentiation.

Future challenges

  • As the market develops, and as applications of graphenes diversify, there may be need for application-specific standards (and regulations), too.
    • For example, the advantages offered by graphene in the construction industry demand review of regulations on the amount of cement required in building materials (looking towards net zero targets).
  • A key future challenge is the democratisation of measurements. ISO standards are at the top of the ‘metrology pyramid’, where there are only a few entities able to measure properties with high accuracy and precision. Whilst the top is the ‘gold standard’, and the ultimate comparator, those measurements are not accessible enough for in-line quality control testing on large batches of material.

  • A final further challenge is to expand standards and to look at more members of ‘family graphene’. Valuable properties are not confined to the extremes of graphene and graphene oxide, and other functionalised or modified graphene-based materials may be cheaper to produce and scale-up. Recognition of these materials, with standardisation, will expand their commercial potential. 

Just as new standards continue to be developed for carbon nanotubes, a technology considered to be at least 13 years older than graphene, we can expect to see the standards for the graphene field continuing to develop and grow.

Standardisation from the Intellectual Property perspective

The evolution in measurements on, and definitions of, ‘graphene’ give scientists and engineers a deeper understanding of, and confidence in, the materials that they use. This encourages investigation into new applications, and into how different properties of graphene affect product performance and characteristics. For that reason alone, we can expect the number of patents filed in this area to expand as standardisation matures.

From the Patent Attorney’s perspective, the standardisation process increases the level of detail we can use to define ‘graphene’ in those patent applications. It can give us features that we can use to argue for novelty and inventive step – so long as we robustly define those measurements and demonstrate a technical effect.

For example (and of course subject to international variation between patent offices!):

  • From the general to the specific

Patent A, describing ‘graphene with a lateral flake size of 1-20 µm” may be considered novel over Patent B describing ‘graphene’ as a general term.
  • Specific, but different

Patent A, describing ‘graphene with a lateral flake size of 1-5 µm’, may be considered novel over Patent B, describing ‘graphene with a lateral flake size of 10-20 µm’.
  • “Selection inventions” – sub-ranges, and selection from lists

Patent A, describing ‘graphene with a lateral flake size of 3-5 µm” may be considered novel over Patent B, describing “graphene with a lateral flake size of 1-20 µm”

Thus, standardisation both encourages innovation and provides us with the tools we need to protect those innovations.

Summary and Outlook

There’s plenty of room for the ‘thinnest and strongest material known to man’ to support new inventions and new patent filings. Standardisation is well recognised to accelerate the commercialisation of new materials, and we’re therefore at an exciting point in the field of graphene research.

If you’re an innovator in the graphene space, then we would love to hear from you.

Key Sources

  1. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1080614/role-of-standardisation-in-support-of-emerging-technologies-uk.pdf 
  2. https://www.npl.co.uk/getattachment/231d2784-3e76-425a-98ac-d79a1b9cd651/npl-ngi-graphene-metrology-whitepaper.pdf?lang=en-GB&ext=.pdf 
  3. https://www.npl.co.uk/graphene/standards 
  4. https://www.mub.eps.manchester.ac.uk/graphene/2021/03/graphene-and-npl-new-standards-for-a-maturing-industry/ 
  5. https://www.graphene-info.com/new-eu-consortium-launched-handle-reach-graphene-registrations