Printed Electronics World regularly covers developments in graphene-based materials. Reports have noted that "the market now accepts the diversity of graphene types and that not all graphenes are equal." In this article, I will provide some perspective on the manufacture of graphene oxide with respect to chemical purity and production sustainability.
As a carbon-based material, graphene is generally safe. However, the manufacturing processes for various graphene-based materials can use hazardous materials such as acids, oxidizing and reducing agents. On a small scale, these chemicals are easily handled. However, when graphene production is scaled the challenge of dealing with large quantities of reactive and corrosive materials is significant.
Recently, thousands of chemical factories in China have faced shutdowns as part of a push to more strongly enforce environmental regulations. Factories producing dyes have been hit particularly hard as their processes typically use large quantities of hazardous materials. In some cases, these are exactly the same materials used for graphene manufacture.
An increased focus on safety is undoubtedly a good news story. Improved sustainability and reductions in hazardous materials benefits everyone, particularly those who work in and live near the factories that use these chemicals. However, this does stand as an important reminder for the emerging graphene industry that reliable supplies will depend on companies building production facilities that can deal with reactive materials and waste on a large scale.
JMC is an example of a chemical company that has built its reputation on the reliable supply of high quality materials. JMC's main product is saccharin, the artificial sweetener. Saccharin is accepted as a safe additive to food, beverages, toothpastes, mouthwashes and pharmaceuticals around the world. JMC's saccharin production facility, in South Korea, handles large quantities of reactive materials every day and has quality controls that ensure that JMC's saccharin is the highest quality in the world.
JMC has recently worked with Dr Yang at the Korea Electronics Technology Institute (KETI) to develop a cost-effective scale-up scheme for the production of graphene oxide and reduced graphene oxide, utilizing expertise in effective handling of acids and regeneration of oxidizing agents. Notably, rather than being a start-up promising scale, JMC is an established chemical company with demonstrated capacity to produce thousands of tonnes per year of high purity materials. JMC is also part of the KISCO group which has deep experience producing ultra-high purity materials for electronics. JMC is also collaborating with KETI on other applications such as polymer-graphene oxide composites and materials for barrier films and displays.
JMC's entry into the graphene-based materials market is a signal that established chemical companies now see graphene as a viable market. This should help to provide the industry with greater certainty around the reliability and consistency of supply. JMC has already identified processes that enable the production of graphene oxide with a range of particle sizes.
JMC is also working closely with Professor Joo from Cornell University to further develop processes and identify potential applications for graphene oxide. Professor Joo will be speaking at IDTechEX on tailoring the folding and stacking of graphene oxide via scalable processes. Professor Joo will discuss results on using gas-assisted electrospinning to tailor the folding of large-sized graphene oxide sheets. These networks can then accommodate the volume expansion of silicon nanoparticles in batteries or be completely flattened to give a conformal coating for applications in corrosion prevention.
Dr Scott Watkins
Chief Marketing Officer, KISCO Group