Optical emission spectroscopy study in CO₂ methanation with plasma

Methanation of CO₂ is a key technology to realize a sustainable society. The reactions should be driven at a lower temperatures from the viewpoint of catalyst stability. Methanation with plasma catalysis can drive reactions at lower temperature than thermal catalysis. However, the reaction mechanism is little understood due to the complexity of the interactions. In this study, we investigated the power and pressure dependence of the methanation efficiency when only plasma is used as a fundamental research. We discuss how these parameters change the vibrational temperature and active species density and affect the methanation efficiency using optical emission spectroscopy.