(54n) Calorimetric Study of Graphene Oxide Thermal Stability

Due to the immense potential of graphene for energy storage and composite filler applications, the large-scale production of graphene is of increasing commercial and academic interest. Synthesis route to produce graphene-like material involving graphite oxide (GO) is predominantly used because this method as shown potential for bulk production at high yield. This method involves the oxidation of graphite to GO and its subsequent reduction to reduced graphene oxide (rGO). However, prior studies have shown that GO can undergo explosive decomposition under certain conditions. There is no documented process safety incident specifically related to GO so far, but GO is an energetic material that can undergo explosive thermal reduction. A number of unanticipated process incidents have occurred due to inadequate study and understanding of energetic materials stored in large quantities. As industry is ramping up large scale manufacturing of GO, the motivation of this research is to investigate potential process safety issues with bulk GO storage and handling. Specifically, we have seen experimental data that increasing GO mass decreases the temperature at which material decomposes, also called T_onset. We have also been able to quantify the pressure release during decomposition. We will further examine the underlying causes of explosive behavior of bulk GO and propose safer storage and handling conditions. Studies are conducted in two calorimeters (Advanced Reactive System Screen Tool (ARSST) and Automatic Pressure Tracking Adiabatic Calorimeter (APTAC)) to understand the effect of storage temperature, impurities, pH, and process conditions on graphene oxide thermal stability. This research will be beneficial in assessing the hazards of GO and enhancing safety of rGO production processes over their life cycles.