A study of reaction mechanisms of methane in a radio-frequency glow discharge plasma using radical and ion scavengers

When 1 Torr of methane was decomposed in a radio-frequency glow discharge plasma, ethane, ethylene, and acetylene were produced as major products. In order to determine the relative importance of radical and ionic processes for the formation of these major products, iodine and ammonia were used as radical and ion scavengers, respectively. It was found that the major products were formed mainly by radical processes and the contribution of ionic processes is within the experimental error. The mechanisms for the formation of ethane, ethylene, acetylene, and C3 ~ C4 compounds were discussed.