Electrically enhanced non-thermal plasma degrading phenol in water

In this study, the influence of electric fields on the degradation of phenol by non -thermal plasma was investigated using density functional theory (DFT) at the M06-2X/6-31+G(d,p) level. The changes in reaction rates of phenol degradation by non -thermal plasmas under different directions of external electric fields were studied. The reasons for the changes in reaction rates were explained by analyzing free energy barriers, dipole moments, frontier molecular orbitals, and van der Waals surface electrostatic potentials based on the total molecular density. The results indicate that, in the model system established in this study, a positive X-axis electric field significantly enhances the rate of phenol removal by non -thermal plasma, while a negative X-axis electric field decreases the rate of phenol removal by non -thermal plasma. As the positive X-axis electric field increases, the free energy barrier and HOMO-LUMO gap decrease, while the dipole moment and electrostatic potential increase. A positive X-axis electric field lowers thermal stability of phenol degradation system, enhancing electrostatic interactions and consequently increasing reaction activity. Conversely, when a negative X-axis electric field is applied, the data show opposite trends to those observed with a positive electric field, indicating that a negative X-axis electric field inhibits the degradation of phenol.