Researchers from the National University of Singapore (NUS) have set out to tackle the issue of a lack of graphene production standards, which leads to many cases of poor quality graphene from suppliers. The team developed a systematic and reliable method for establishing the quality of graphene samples from around the world. They were able to achieve this by using a wide range of analytical techniques and tested samples from many suppliers.
Upon analyzing samples from over 60 different providers from the Americas, Asia, and Europe, the NUS team discovered that the majority contained less than 10% of what can be considered graphene flakes. The bulk of the samples was graphite powder that was not exfoliated properly.
Just one of the samples tested in the study contained more than 40% of high-quality graphene. Moreover, some samples were even contaminated with other chemicals used in the production process. These findings mean that researchers could be wasting valuable time and money performing experiments on a product that is falsely advertised.
This is the first-ever study to analyze statistically the world production of graphene flakes. Considering the important challenges related to health, climate, and sustainability that graphene may be able to solve, it is crucial that research is not hindered in this way, explained Prof Castro Neto.
With this discovery and the development of a reliable testing procedure, graphene samples may now be held to a higher standard. We hope that our results will speed up the process of standardization of graphene within ISO as there is a huge market need for that. This will urge graphene producers worldwide to improve their methods to produce a better, properly characterized product that could help to develop real-world applications, said Prof Castro Neto.
In addition, testing graphene using a universal and standardized way could ensure easy quantitative comparisons between data produced from different laboratories and users around the world.