Investigation On The Effect Of Dielectric Material On Bipolar Nanosecond Pulse Dielectric Barrier Discharge At Atmospheric Pressure

Dielectric barrier discharge is one of the simplest ways to generate homogeneous non-equilibrium plasma. The plasma is characterized by low temperature, moderate particle density, which has tremendous application on biomedicine and surface modification. In this study, a bipolar nanosecond pulse power supply is employed to generate diffuse low temperature plasma using needle-plate configuration in air at atmospheric pressure. The attention is paid on the effect of dielectric material on the nanosecond pulse dielectric barrier discharge plasma. The main results gained in the experiment have been summarized as follows:1. The diffuse dielectric barrier discharge plasma is successfully gained by bipolar nanosecond pulse power supply using needle-plate electrode in air at atmospheric pressure. The effect of dielectric material on the discharge homogeneity and emission intensity of N2(C3Πuâ†'B3Πg,0-0,337.1nm) is investigated. The effects of pulse peak voltage and gas gap distance on the emission intensity of N2(C3Πuâ†'B3Πg,0-0,337.1nm) and plasma area on the dielectric surface are studied. Results show that the emission intensity of N2(C3Πuâ†'B3Πg,0-0,337.1nm) is stronger with a poor discharge homogeneity while ceramic is used as dielectric material. The emission intensity of N2(C3Πuâ†'B3Πg,0-0,337.1nm) and plasma area rise with the increase of pulse peak voltage, but decrease with the increase of gas gap distance.2. The optical emission spectra of N2(C3Πuâ†'B3Πg,0-2)å'ŒN2(C3Πuâ†'B3Πg,1-3) are used to calculate the plasma gas temperature by Specair. The plasma gas temperature is357K,340K and315K when ceramic, quartz and PTFE are used as dielectric plate, respectively.3. Nanosecond pulse dielectric barrier discharge plasma is successfully gained in nitrogen at atmospheric pressure. The spatial distributions of N2(C3Πuâ†'B3Πg,0-0), NO (A2∑â†'X2Π)å'ŒOH (A2∑â†'X2Π,0-0) are investigated. It is found that the emission intensities decrease from the needle electrode to plate electrode while a slight increase appears near the plate electrode.