Low cost, industrial scale, high-quality CVD graphene production

Oct 14, 2021 | Articles, Knowledge Center

Graphene, regarded as a “wonder material” since its discovery in 2004, has been kept in the lab for almost twenty years. However, its potential has now been unlocked by developing cost-effective, high-quality CVD graphene. With a thickness of only one atom, graphene has been the subject of numerous theoretical experiments that have demonstrated its extraordinary properties, such as:

  • Ultrathin (.345 nm);
  • Young’s modulus of 1 Tpa;
  • Intrinsic tensile strength of 130 GPa (>200x stronger than steel);
  • Thermal conductivity > 3,000 WmK (graphite is 2,000 WmK);
  • Optical absorption of exactly πα≈2.3% (i.e., transparent);
  • Impermeable barrier to all gases;
  • Room temperature electron mobility of 200,000cm2/(V·s) (silicon is 1,400 cm2/(V·s));
  • Breakdown current density of 107 A/mm-2 (copper is 1,000 A/mm-2); and
  • Transparent
  • Chemically inert
  • Biocompatible

Quite simply, graphene is among the strongest, thinnest, and most conductive materials known to man. Graphene’s potential is limitless, with suggestions that it could be used to produce clean water, rechargeable batteries that last for days, and even a space elevator. It is no surprise that Professors Andre Geim and Konstantin Novoselov, who discovered graphene, were awarded the Nobel Prize for Physics in 2010.

An Unsettling Contrast

Graphene has undergone extensive research, possibly more than any other material in history. However, despite almost two decades of investigation, we are faced with an unsettling contrast: while the properties of graphene are undoubtedly real, they are also severely misleading. It is currently impossible to produce “pristine graphene” on a practical scale under real-world conditions (at least for now). Additionally, the production of graphene is complex and costly. Its technical and commercial potential, which was once thought to be limitless, has caused some to regard it as a mere illusion. In fact, the excitement surrounding graphene has arguably resulted in more disappointment than optimism.

Certainly, an individual with even a basic knowledge of history could easily present a lengthy catalog of strongly held beliefs that were ultimately discovered to be not only inaccurate but entirely false – such as the idea that the Earth is flat, or that the Sun orbits the Earth, or that stress leads to ulcers, and so on. However, this is not the situation with graphene. Through scientific inquiry, we have been able to recognize and analyze graphene, and to comprehend its hypothetical possibilities. Yet, scientific inquiry alone is insufficient to transform those possibilities into reality.

Our present era is marked by intricacy and disarray, and there are limits to what we can discern or prognosticate. However, the natural order eventually becomes evident and the disorder often becomes insignificant in comparison. A few individuals perceive this reality, but the majority do not. The experiences of Adam Smith, Charles Darwin, and Albert Einstein serve as clear examples that although they were not always able to provide a flawless explanation, they possessed a greater comprehension of the order that exists in nature than most people.

Defining science

In a speech to the National Science Teachers Association in April 1966, Richard Feynman, who was mentored by Einstein, proposed a method for encouraging students to adopt a scientific mindset, which involves being open-minded, inquisitive, and above all, skeptical. In his lecture, he offered a definition of science that was derived from multiple stages, including the development of intelligent life on Earth, which resulted in creatures like cats that play and learn from experience. He also mentioned the emergence and evolution of humans, who began using language to transfer knowledge from one individual to another and to preserve information for future generations.

It is possible for both accurate and inaccurate information to be transmitted through generations, making it necessary to take additional measures. This led Galileo and others to begin questioning the validity of knowledge passed down and to start exploring from the beginning, based on experience, to uncover the true reality. It was from this process that the concept of science emerged. Feynman defined science as a means to gain a clear understanding of the inherent order in the universe, provided that we possess an open-minded, curious, and skeptical attitude toward our existing knowledge.

Plenty of room at the bottom

In 1959, Feynman delivered a speech to the American Physical Society called “Plenty of Room at the Bottom,” which centered on the issue of managing and regulating things on a small scale. This address is often regarded as the genesis of nanotechnology and continues to provide crucial insights into comprehending the world we live in. It is especially useful in understanding graphene. Feynman himself described the focus of the speech as dealing with the problem of manipulating and controlling things on a small scale.

In his speech, Feynman expressed his willingness to contemplate the possibility of manipulating atoms as we desire in the distant future. He posed the question of what would happen if we could place atoms one by one in the exact positions we desired, with the caveat that we cannot arrange them in chemically unstable configurations beyond practical limits.

Feynman posed the question of what we could achieve if we had layered structures with precisely arranged layers. He speculated about the possible properties of materials if we could manipulate atoms as we desired and expressed his interest in exploring these theoretical possibilities. Although he couldn’t predict with certainty what would happen, he believed that having some control over the arrangement of things on a small scale would vastly expand our capacity to do new things and create substances with novel properties.

“Atoms on a small scale behave like nothing on a large scale, for they satisfy the laws of quantum mechanics. So, as we go down and fiddle around with the atoms down there, we are working with different laws, and we can expect to do different things.”

Graphene is undoubtedly the material that Feynman was referring to, but it is just the beginning of numerous nanomaterials to come. The implication is that the future Feynman imagined is now a reality. Although graphene is still in its early stages, we now have the capability to manipulate atoms individually as desired. The technology we use may seem primitive in the future, but it is worth noting that we sent a man to the Moon using less advanced technology than what is available on most smartphones today.

General Graphene

General Graphene Corporation was established with the sole purpose of unleashing the potential of graphene, using a few evident (yet nuanced) facts:

  • The initial stage in utilizing any new substance is creating a method to efficiently manufacture it on a larger scale at a lower cost. The concept of “industrial scale” is essentially interchangeable with “lower cost”;
  • The process of mass-producing graphene is not a scientific obstacle, but an engineering one; and
  • Graphene is not a material that can be used in a one-size-fits-all manner. Similar to a metal alloy, its characteristics can be enhanced and modified flexibly to cater to specific applications, and when paired with other materials, graphene often results in extraordinary enhancements to the latter’s properties.

For a while, graphene has been a subject of significant confusion due to its existence in two chemically identical but essentially distinct forms:

  • ‘Top-down’ graphene, which is derived from exfoliated graphite; and
  • ‘Bottom-up’ graphene, which is produced through chemical vapor deposition (CVD).

Although other types of carbon, such as graphite and diamond, share an identical chemical composition, they have never been mistaken for each other. In contrast, the two forms of graphene are often grouped together as if they were the same, despite having different characteristics. Exfoliated graphite, which is often referred to as a “sheet,” is actually a black powder consisting of granules that are typically less than a few microns in size. On the other hand, CVD graphene is a transparent, unbroken film that can measure in square meters, although samples measuring 100 square centimeters are more common. Even though both forms of graphene exhibit impressive properties, anyone familiar with them would not confuse one for the other.

Acquiring Graphene

Regrettably, the conventional CVD method has been sluggish in the past. Due to the size constraints of the quartz tube, only limited amounts of graphene can be generated, and each batch is a distinct and independent process, making it extremely costly. In essence, traditionally synthesized CVD graphene is incompatible with modern industrial processes, which require high production rates, consistently reproducible outcomes, and low costs. Transforming a batch process into a continuous production line posed a significant obstacle, but as with most innovations, simplicity turned out to be the solution.

The main objective behind the creation of General Graphene was to transform the CVD process into an industrial-scale operation. As mentioned earlier, the company realized this was the only practical approach to attain lower costs and satisfy commercialization requirements. General Graphene has developed a patented and exclusive atmospheric pressure CVD method that can produce high-quality graphene sheets in a roll-to-roll format at a high volume and low cost consistently. It’s worth noting that the company is the only graphene producer that doesn’t employ a traditional quartz tube.

Initially, we exhibited our process on a modular pilot production machine and then optimized it for scalability. Currently, our production machine measures over 21 meters in length and can generate a graphene film that is 300mm wide and can be customized to any length. We can operate the machine continuously since our energy consumption is minimal when operating at a stable state. Our process involves inputs and outputs that are almost indistinguishable, with the latter containing a minimal amount of water vapor and CO2. We don’t use any harsh chemicals, and everything we produce is either biodegradable or recyclable.

Leading Innovation

Our process enables us to tailor the graphene to accentuate the properties required to meet specific application demands. We understand that we only contribute one component to each application development project we engage in – we are proficient in graphene, while our commercial partners are knowledgeable about their applications. It is only by combining our expertise that we can create solutions that leverage all of graphene’s potential, leading to the next generation of products that graphene research has long promised. Application development is an incremental process that necessitates some patience but has enormous potential in helping us and others uncover genuinely unique graphene solutions.

At General Graphene, we are rapid, targeted, and adaptable, recognizing that incorporating cost and performance (as opposed to performance alone) is a critical aspect of fostering innovation.

If you are interested in realizing the potential of graphene, we encourage you to get in touch with us today.

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Originally posted on Innovation News Network. See the original article page here.
Please note, this article will also appear in the eighth edition of Innovation News Network’s quarterly publication.