Interaction effect of adjacent pores on plasma generation inside pores of porous catalysts

Abstract

A study on the influence of pore characteristics on the microdischarge plasma inside pores of catalyst is important for understanding plasma catalysis mechanism. This article focuses on the effect of pore interaction on plasma production in pores including electron density, electron temperature, and total ion density, etc. These parameters are calculated by solving the electron energy density conservation equation, electron convection diffusion equation, heavy species conservation equation and Poisson equation. The numerical simulation results show that the distribution of electron density, electron temperature and electric field in and near a pore is apparently affected by the adjacent pore, namely, the time-averaged electron density, total ion density and ionization rate in a pore increase with the pore spacing in the range of 8–150 μm because the loss of electrons to the wall due to the adjacent pore decreases with the increasing pore spacing, but there is an opposite law for the time-averaged electron temperature and electric field in a pore; moreover, the pore spacing presents more apparent effect on the plasma generation in a smaller pore and at higher applied voltage, indicating stronger interactions between pores at these conditions. The simulation results show that the pore characteristics of porous catalysts including pore spacing and pore diameter may affect the degradation of pollutants in plasma catalysis processes. The study is important for understanding the plasma catalysis mechanisms, especially the influence mechanism of pore interaction on microdischarge in porous catalysts.