介质阻挡放电中氢分子的光谱特性

Investigation on spectral characteristics of H_2 in dielectric barrier discharge

为揭示介质阻挡放电氢等离子体中氢负离子的形成过程和规律,采用发射光谱技术研究了氢分子振动、转动温度以及对H-离子的影响。基于Fulcher跃迁的理论模型,计算了不同振转温度时的谱线强度分布,验证了实验测定结果。在气压70 Pa、电压12 kV、频率30 kHz,运用(0-0)带与(1-1)带谱线强度比计算出振动温度为2 700 K,利用(0-0)带的五条谱线求得转动温度为400 K。当放电频率由10 kHz增加到22 kHz时,振动温度由1 560 K增大到3 900 K,相应的氢离子质谱信号强度也逐渐增大。振动温度的增加是导致氢负离子浓度增大的重要原因。该研究可以用于介质阻挡放电氢等离子体中的振转分布提供一定的参考。

This paper is aimed at identifying the formation process and rule underlying H-ion in dielectric barrier discharge hydrogen plasma. The targeted research consists of investigating the vibration and rotational temperature of hydrogen molecules and their effects on H-ions using optical emission spectrometry; calculating the intensity distribution of spectral lines at different rotational temperatures; and comparing the calculation with the experimental results; in the presence of the discharge conditions（ gas pressure 70 Pa,30 kHz,12 k V）,the vibration temperature calculating to be 2 700 K using the intensity ratio of（ 0-0） band and（ 1-1） band spectrum line; calculating the rotation temperature to be 400 K using five bands of（ 0-0） band. The results demonstrate that the discharge frequency increase from10 kHz to 22 kHz suggests the vibration temperature increase from 1 560 K to 3 900 K,together with a gradual increase in the corresponding signal intensity of hydrogen ion mass spectrometry; and the increase of temperature is an important reason for the increase of hydrogen anion concentration. This study may provide a certain reference for the vibrational distribution of H-ion in dielectric barrier discharge.