A research collaboration between The University of Adelaide in Australia and the National Physical Laboratory has led to the development of a validated analytical tool, thermogravimetric analysis (TGA), for the characterization and quality control of FLG and non-graphene impurities in powder form. TGA is typically used to assess and characterize the thermal properties and impurities of minerals, polymers, and carbon materials. However, its was found to have potential for use as a characterization tool for regulating the quality of graphene materials.
Now, this affordable, simple and reliable method of analysis could be used to improve the quality control measures used in the graphene industry.
The study, led by Farzaneh Farivar, illustrated the efficacy of utilizing TGA for qualitative and quantitative analysis of graphene materials, which could be the basis of quality control of these materials on the market, further decreasing the spread of ‘fake graphene’.
TGA is a method of thermal analysis that can assess the changes in physical and chemical properties through temperature increases. The team's research helped establish a baseline of TGA and first derivative (DTG) characteristics of bulk graphene powder forms with specific analytical parameters being set for reliable quality control of graphene materials. The team recognized differences between FLG and ‘fake graphene’ using samples such as FLG, reduced graphene oxide (rGO), and graphene oxide (GO).
This research illustrated that that FLG, graphene oxide, and graphite powders have distinctive graph peaks and have a temperature of maximum mass decomposition rates found to be in specific ranges. The use of TGA enables the structural, chemical, and thermal differences to be quantified between the different powders, which further signifies the efficacy of utilizing this analytical method as a quality control tool.
Using this method, graphene manufacturers could ensure the industrially produced graphene powders they are trading meet the quality regulations of graphene materials rather than ‘fake graphene’, ensuring the product retains the appropriate properties expected of graphene.
A quality control method such as TGA is an affordable and reliable approach used by small start-up companies attempting to disrupt the graphene industry. This regulation method can be added to the current guidance provided by the ISO to ensure ‘fake graphene’ materials do not overtake this novel market, hindering the growth of the graphene industry and the advancement of technology as a whole.