In the 1967 film The graduate, Dustin Hoffman plays a recent college graduate trying to figure out what to do with his life. His graduation party includes a famous Bradley scene where a family friend takes him aside and offers sage advice: “I just want to say one word to you. Just one word.” The word? “Plastics,” with the older man further warning that “there is a great future in plastics.” If COSM 2023 is right, then if The graduate have been remade today, that one word could very well be “graphene”.
Previous COSM conferences have covered graphene (see here and here), and COSM 2023 hosted a panel on “The Graphene Revolution” with energy entrepreneur Ariel Malik, Bradley Larschan, CEO of Avadain, and Kevin Wyss, who recently earned a PhD in chemistry at Rice University studying with Professor James Tour.
Wyss opened the panel by explaining that graphene is carbon bonded into a single thin sheet in a honeycomb-like pattern – which is extremely strong, stable and conductive. These special properties enable applications such as strengthening cement or plastics, manufacturing flexible electronics, and stabilizing next-generation batteries.
Yet Another Use for Duct Tape
Graphene was first characterized in 2004, when two researchers took graphite – essentially sheets of layered graphene – and exfoliated individual sheets of graphene using scotch tape. In the multilayer form of graphite, carbon loses its special conductive properties and strength, becoming brittle. But Wyss explained that “if you take a layer of graphite and turn it into graphene, you get something very strong and special.” This seemingly simplistic “top-down” method of producing graphene earned two scientists the Nobel Prize in Physics in 2010.
Another method, called “bottom up”, seeks to build graphene from some carbon-based source material.
As is often the case, different methods have advantages and disadvantages. The top-down method produces large graphene sheets at low cost, but it is difficult to obtain large defect-free graphene sheets. Therefore, it is cheap but of low quality. The bottom-up method provides higher quality graphene, but the sheets are smaller and more expensive; It is high quality but expensive.
Graphene’s “Aluminum Moment”
Is there a way to create high-quality graphene at low cost? Wyss explained that graphene recently went through an “aluminum moment.” A little history of materials science explains what this means and how it changed the world.
In the mid-19th century, aluminum was seen as a promising metal for technological applications due to its light weight and high strength. But at that time aluminum was difficult to extract, making it more expensive than silver. Then, an electrolysis method was developed to extract aluminum and its price fell by 96% in just over a decade. We may not appreciate the importance of these innovations in materials science today, but Wyss explained that the ability to extract aluminum at low cost has allowed us to build airplanes and led to the modern world of global transportation. “Aluminum,” said Wyss, “has become a symbol of modernity.”
Now the good news
The moment for graphene aluminum may have already arrived – and it came at the hands of Professor James Tour. Called “flash graphene,” Tour’s method takes carbon-based material, quickly heats it using an electrical current, and produces high-quality graphene at a very low cost. Forbes described this research with the following title: “Innovative method for making graphene from waste is modern alchemy”.
There are other benefits. Flash graphene works well with plastics, but plastics only contain 80-90% carbon. Plastics also contain 5 to 14% hydrogen in addition to oxygen. Wyss explained that during the graphene flash process, his research discovered that a useful byproduct is clean hydrogen, which has many applications, including serving as a fuel source.
While flash graphene holds great promise, Bradley Larschan explained that because it uses the “bottom-up” method, it does not produce large flakes of graphene that have special applications. Through an electrochemical exfoliation process, Larschan observed that large pieces of high-quality graphene can be extracted from graphite. These large parts have many important applications, including aviation (where aircraft weight can be reduced by a third), electric vehicles (again, allowing for lighter materials) and defense (producing ballistics-proof materials). He further noted that graphene can be used as a supercapacitor, which could allow electric vehicle batteries to be charged more quickly.
Competition is not a problem
Entrepreneur Ariel Malik noted that carbon nanomolecules also hold great medical promise, as they have been used to quickly repair severed spinal cords in rats. In light of these promises, Larschan made the comparison between graphene and “plastics” in The graduateshowing that graphene can revolutionize many forms of technology.
So, with Wyss promoting bottom-up flash graphene and Larschan touting the benefits of top-down graphene, which method is superior? The panel seemed to agree that they are not in competition because they target different niche markets and have different beneficial applications. Furthermore, as George Gilder said, competition from graphene is not a problem because “it is the biggest market opportunity in the world”.