Mechanochemical Degradation of SF6 for Realizing Simultaneous Disposal of Super Greenhouse Gas and Manufacture of Fluorinated Graphite Materials

Abstract

As the most potent greenhouse gas, SF6 can cause persistent harm to the environment if discharged directly to the air. Therefore, it is necessary to develop an efficient approach for its disposal and resource utilization. Here, we discovered the mechanochemical degradation of SF6 by graphite under mild conditions, along with the formation of an S-containing fluorinated graphitic carbon material (SFGCM) with over 8% of sulfur and 12% of fluorine, being a “one-stone-two-birds” strategy. The unexpected reaction between SF6 and graphite with least reactivity may be ascribed to the intensive mechanical stress and grinding on graphite for its size miniaturization and radical formation at the cutting edges, as well as their synergistic activation for SF6. The resultant SFGCM is composed of few-layered graphite nanomaterial with rich porosity, high specific surface area (380 m2 g–1), good amphiphilicity, and excellent adsorptivity for heavy metals (Hg2+) from aqueous solution. This study provides a viable way for the resource utilization of SF6, and sheds light on the massive degradation of various greenhouse F-gases in the future.