Synergistic regulation of charge state and electron-donating ability via heterojunctions design for fixation of electronegative greenhouse F-gases

Abstract

The net-zero greenhouse gas emission has now become a global strategy. In this context, electronegative fluorinated-gases such as sulfur hexafluoride (SF6) and hydrofluorocarbon, have become important emission reduction objects due to their strong global warming potential. In this work, the MnOx@Mn/SiC heterojunction was rationally designed and prepared. Because of the high electron coupling, the positively charged active-site MnOx@Mn (δ+) not only promotes the adsorption of SF6 but also acts as a donor to transport electrons to SF6, so that the adsorption and activation of SF6 are unified in one active site. Therefore, MnOx@Mn/SiC can effectively degrade SF6 above 450°C, and the degradation amount for 12 vol% SF6 can reach 523.8 mL g−1 at 600°C. Furthermore, it also has good degradation performance on hydrofluorocarbons (R-22 and R-410A) even at 100°C. Given the cheap and easy scale-up synthesis, MnOx@Mn/SiC has the potential to reduce the emission of multiple fluorinated-gases in practical applications.