Recent advance of atomically dispersed catalysts for direct methane oxidation under mild aqueous conditions

The direct methane (CH4) oxidation to high-value chemical products under mild aqueous conditions is a promising energy-conversion technology to fulfill the urgent demand of varied industrial feedstocks and the efficient utilization of vast CH4. Developing advanced catalysts to activate C–H bond and inhibit peroxidation of desired products is extremely pivotal to realize the direct CH4 oxidation with high activity and selectivity. Recently, atomically dispersed catalysts gradually show an excellent catalytic performance on the direct CH4 oxidation process due to their unique atomic structure, high metallic utilization, and modulated coordination environment. In this review, the experimental and theoretical progress of atomically dispersed catalysts for the direct CH4 oxidation is summarized, and in particular, the influence of atomically dispersed catalysts with different supports (metal oxides, carbon materials, metal-organic frameworks, and molecular sieves) on catalysts design, theoretical calculation, the C–H activation mechanism, as well as inhibition mechanism of peroxidation are emphasized. Finally, the immense opportunities and challenges for atomically dispersed catalysts on the direct CH4 oxidation are discussed, and some insights into the development of atomically dispersed catalysts are provided.