| Summary: | Large reserve of methane, in the form of natural gas and methane hydrate, has been discovered and it has been intensively used as a fuel, or as a building block for the chemical synthesis. However, severe environmental and climatic issues caused by the leakage of methane during the production, transportation and use of methane are overlooked. This offers incentives for the catalytic removal of methane. Nevertheless, due to the inert nature of methane molecules, the activation of methane via thermocatalysis requires harsh reaction conditions. The high reaction temperature not only increases the capital cost but also accelerates the deactivation of catalysts due to sintering and/or coking. The development of robust and stable catalysts with a low operating temperature has become the focus of the research on thermocatalytic methane oxidation. Photocatalysis, which uses the energy of photons instead of heat to drive chemical reactions under ambient conditions, offers another approach to methane removal. This review will cover the development of high-efficiency catalysts for methane combustion in both thermo- and photocatalysis. Moreover, the fundamental understanding of the active sites, surface chemistry and reaction pathway will also be discussed. Finally, the challenges facing in the catalytic removal of methane will be summarized and potential solutions will be provided. This review will be of interest to researchers in the field of heterogeneous catalysis, materials design, and chemical engineering.
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