Self-driven microplasma decontaminates chemical warfare agent simulant in different gas environments

Abstract

To develop and refine a self-driven plasma decontamination system, this study investigated the effect of different gas environments (air, Ar, Ar/O2, and Ar/O2/H2O) on the degradation efficiency of 2-chloroethyl ethyl sulfide (2-CEES). A dielectric-dielectric rotating triboelectric nanogenerator (dd-rTENG) was constructed to mechanically induce atmospheric plasma. The dominant active species of different plasmas were identified through spectroscopic and chemical probe diagnostic methods. The results revealed that Ar/O2 and Ar/O2/H2O plasmas generated higher levels of reactive Ox species (O3, O2-, and 1O2) and OH radicals, respectively. Notably, the Ar/O2 and Ar/O2/H2O plasmas exhibited significantly higher decontamination efficiencies than the other plasmas. Moreover, the Ar/O2/H2O plasma featured an energy utilization efficiency of 0.962 μg/J, which is nearly twice that of the previously reported study. However, the Ar plasma exhibited minimal decontamination effect owing to its low electron energy and absence of active species. Further studies have indicated the vital role of reactive oxygen species in the 2-CEES decontamination process. Active Ox can promote the oxidation of 2-CEES, while OH can effectively mitigate the peroxidation process. Furthermore, the system exhibited low electron energy, which might play small role for 2-CEES decontamination. This study is vital for developing self-driven plasma decontamination devices and provides significant clues for understanding the 2-CEES decontamination mechanism.