Graphene quality and pricing improves with maturing supply chain
Jul 15, 2015
At IDTechEx we have invited a number of leading players in the graphene industry to write opinion pieces, reflecting on their products , latest research, market insight, and commercialisation experience. We will be releasing these articles over the next few weeks.
This article is by Dr. Francis Nedvidek of NanoXplore, a Montreal-based company specializing in the unique science of graphene and its derivative materials.
Literally billions of $, €, ¥, £ and ₩ are flowing into research, application development, production and deployment of the recently "isolated" wonder material graphene. Consumer electronics and energy storage were first among a burgeoning assortment of prospective killer apps anticipated from automotive, paint and coatings, aerospace, communications, 3D printing, filtration, sensing, solar energy, lubricants and oil extraction sectors to find commercial application. In spite of generous investment and a profusion of activity, rewards garnered from graphene have so far been rather modest.
Graphene burst onto the scene with great promise and potential. Indeed, graphene achieved initial notoriety via new touch screens, better batteries and a varied assortment of products fabricated using graphene composites. Never-the-less anecdotal evidence suggests, that the majority of young products are operationally unprofitable. Graphene ventures remain securely tethered to the in-house- needs and deep pockets of parent corporations or supported by enthusiastic high-tech investors.
Graphene by definition consists of a 2-dimensional atomic scale carbon honeycomb lattice - or chicken wire. "Bottom up" fabrication processes, such as chemical vapor deposition, yield large and high quality graphene plies. All "top down" methods essentially cleave atomic layers from naturally occurring bulk graphite. Achieving desired delamination of individual nano-scale graphene platelets critically depends on process IP and confidential technique. Graphene flake available on the open market today typically comprises sheaths from one to a several adhering layers with average platelet size of approximately 1 um. These two metrics, thickness and size determine to a largest extent determine quality.
My purpose is to step back from popular hype, financial market exuberance (or pessimism), and science fiction to gain a sober perspective of the state of affairs for the top down regime of graphene suppliers.
Quantity, Nomenclature and Reliable Supply
The benefits and the challenges of producing and subsequently harnessing graphene refined from graphite (top down) remain formidable for applications demanding industrial quantities of few (below 6) layered, large area (average diameter of greater than 1 um) flake. The issues are:
1. Difficulty scaling to efficient, sufficient and consistent production levels for high quality (few layer large diameter) graphene. Lack of stable and high quality supply erodes broader commercial viability and represents the first obstacle along the road to commercialization;
2. The second hurdle arises from the first: the insufficient supply of high quality graphene at economically feasible cost points encourages or forces - intentionally or surreptitiously - use of poorer quality graphene. For the purposes of this article, high quality graphene contains on average less than 6 layers and / or an average platelet size of greater than 1 um. In extreme cases, users may decide to switch from graphene to forms of graphite consisting of graphite particles containing from 6 to many 10's of single carbon layers or expanded graphite;
3. Graphene is not graphite - the present nomenclature obfuscates and confuses. Extracted from the earth and refined to yield a variety of particles of various sizes and shapes, graphite is orders of magnitude less expensive than graphene and performs quite adequately for many applications. Graphite of course cannot enable the atomic scale and nano dimension superlative physical, chemical, electrical, thermal, barrier and bio-interaction properties exhibited by graphene. Particularly demanding applications such as touch screens utilize pristine, continuous and defect free cm2 expanses of single layer graphene film. Regarding graphene flake, many experts hold the opinion that applications using substrates such as polymers, resins and oils, dispersion of graphene flake thicker than 5 layers forfeits a vast majority of desired behavior and characteristics. Again, this is not to say that graphite is not useful and perfectly adequate for many applications. However, alternatives for applications demanding high quality graphene flake are at best still in the research labs.
4. Development and exploitation of graphene and its derivatives is a nascent field and, though expanding rapidly, remains immature. The graphene ecosystem, besides obvious supply and availability issues, suffers from undeveloped standards and nebulous regulation. Essential test protocols and characterization metrics do not yet exist. This deficiency of uniformly administered standards and trusted certification agencies impedes market transparency and hinders collaborative development, both scientific and commercial. Even as graphene supply gradually satisfies demand in terms of quality and availability, prolonged lack of a certification system will dampen investment and longer-term growth.
5. Threats to health and safety concerning new materials have too often been overlooked in the past. Graphene producers seem to take the risk in stride. Concerns regarding graphene toxicity could profoundly impair adoption of graphene for a wide swath of applications including composites and additives intended for consumer and non-professional deployment. "We don't want another asbestos public health calamity" resonates with the legal counsels of major corporations as with institutional investment funds and workers' unions. Experts studying the toxicology of graphene have found no reason to sound alarms.
Never the less, several years of further investigation will be needed before publishing conclusive findings. The moral, socially responsible and economically expedient reaction mandates complete co-operation with safety organizations, biomedical researchers and legislators. Cooperation will hasten introduction of clear metrics and guidelines for graphene. Dealing openly and expediently with health concerns will quell worries and permit useful progress. For the time being, graphene must be handled with the precautions reserved for hazardous materials.
Novel Substance, New Recipe, Higher Expectations
As mentioned above, contemporary characterization of "graphene" adheres to no broadly systematized methodology or norms. The marketing of graphene therefore does not - and in the current situation cannot - abide by standards dictating identification or classification according to number and size distributions of graphene platelets. Neither impurity content, nor surface defect rate follow to agreed guidelines. Practicable functionalization metrics essential for advanced processing and sophisticated mixing and compounding have yet to be established. Since characterization has stalled - graphene suppliers, as a group, need to act.
OEMs dispersing graphene directly into commodity or proprietary polymer recipes for injection molding applications, compounders creating special formulations to address their customer' applications, or product development labs endeavoring to exploit one or more of graphene's unique properties, all share a common challenge: Each of these "users" employ trial-and-error in determining whether graphene, graphene oxide, a particular variety of reduced graphene or some other functionalized derivative best addresses the intended enduses. Thereafter, repeated iteration - adjusting, testing and analysis - typically in tight collaboration with a specific graphene vendor, helps identify formulations satisfying the desired operational, physical, chemical / physiological and of course economic requirements.
In many instances, subsequent stages of the value chain come into play: for example when a graphene source sells to a compounder, which in turn delivers formulations to injection molding shops which ships components to automobile OEMs. Each stage imposes different - usually aligned but sometimes competing - demands. Development and commercialization programs aimed at making profits by exploiting benefits of graphene, must endure a potentially long, complex and expensive journey.
Being such a novel ingredient, product develop labs must contend with a dearth of empirical measurement and minimal practical experience. Dispersing or otherwise mixing graphene is not necessarily difficult but may demand training and support instruction. One such notional trap is ignorance of the fact that addition of even miniscule quantities of graphene (say adding graphene to polymers for molding parts) typically induces disproportionate changes to the targeted product parameters. Seeding standard polymers with less than 1 % reduced graphene flake often substantially modifies thermal conductivity, electrical conductivity, UV endurance, abrasion resistance and possibly even imparting of antimicrobial qualities. The same disproportionate effects may be observed with silicones, lubricants and coatings.
Beyond substitution and thinking outside of the box
Modern process driven product innovation often draws from a plethora of long-established ingredients backed by myriad technical data, taking advantage of proven fabrication methodologies brought to life via structured, efficient and well established product development pipelines. Presently, graphene vetting and the evaluation of resulting compounds or end products is very much exploratory. This speculative process is inordinately time consuming and does not mesh well with the "goal oriented" approaches of product development organizations. The arduous development "distillation" process may extend across several value creation stages, protracting an already long, slow and expensive "pipeline", delaying market introduction and ultimately eroding payback for customers and stakeholders alike. Motivation wanes and young enterprises desperate for cash flow suffer and risk death unless supported by generous and patient investors.
Perfunctory "switching in" graphene risks killing new product attempts in two major ways: first, the precise physical / chemical profile as well as the amount of graphene introduced fails to generate the desired results by a wide margin. Even in the planning stages, misunderstood loading inadvertently triggers aborting of new product investigations on grounds of graphene's poor cost competitiveness vs. the substituted materials. New formulations run into an irreconcilable cost disadvantage caused by misguidedly assuming that graphene in amounts remotely comparable to that of the substituted constituent(s) need to be used. Consideration that more reliable graphene suppliers enter the market, improving production processes and appearance of standards will contribute to mitigate the total costs of grapheme and graphene derivatives.
Collectively, development chemists and application specialists regard graphene foremost as a replacement for one or more presently available and currently used constituents. Incumbent "solutions" comprise well-understood, often low cost and readily available formulations, additives and compounds. Additionally ignored are concomitant product benefits and other process or cost savings made possible by reducing or eliminating other additives or compounds from the recipes. Finally, enhancements and new attractive attributes accompanying a move to incorporate graphene into product recipes may never be realized and appreciated. Companies fail to monetize customers' cost of ownership advantages and thus fail to capture higher margins or greater market share enhanced image not to mention increasing longer-term attractiveness of many business cases owing to an inevitable fall of graphene prices.
The entire value chain needs to escape the single-minded drive to the lowest common denominator: graphene should be seen primarily as an enabler and an opportunity to create what previously did not exist or was not possible.
To sum it:
1) Availability and quality of graphene will gradually improve and costs inevitably fall;
2) Industry standards are desperately needed and suppliers should take collective action to remedy the situation;
3) The health and safety concerns must not be ignored rather clarified as quickly as possible;
4) The supply chain needs better knowledge and training regarding the handling, mixing and application of graphene;
5) Widespread adoption of graphene hinges on intensive collaboration, co-operations and partnerships throughout the value creation chain;
6) The entire value chain must resist the temptation to drive to the lowest cost common denominator;
7) All stages of the value creation chain from graphene suppliers through to formulators, compounders, mixers, molders and fabricators, OEMs and distribution partners must equip themselves to effectively communicate performance differentiation and resulting benefits / advantages for consecutive contributors in the value chain.
8) Product development specialists must think beyond cost savings of status quo business cases. The focus must be the new products and disruptive applications of the amazing and unique potential of graphene.