Current Progress on Methods and Technologies for Catalytic Methane Activation at Low Temperatures.

Methane (CH ) is an attractive energy source and important greenhouse gas. Therefore, from the economic and environmental point of view, scientists are working hard to activate and convert CH into various products or less harmful gas at low-temperature. Although the inert nature of CH bonds requires high dissociation energy at high temperatures, the efforts of researchers have demonstrated the feasibility of catalysts to activate CH at low temperatures. In this review, the efficient catalysts designed to reduce the CH oxidation temperature and improve conversion efficiencies are described. First, noble metals and transition metal-based catalysts are summarized for activating CH in temperatures ranging from 50 to 500 °C. After that, the partial oxidation of CH at relatively low temperatures, including thermocatalysis in the liquid phase, photocatalysis, electrocatalysis, and nonthermal plasma technologies, is briefly discussed. Finally, the challenges and perspectives are presented to provide a systematic guideline for designing and synthesizing the highly efficient catalysts in the complete/partial oxidation of CH at low temperatures.