Direct Methane Conversion under Mild Condition by Thermo-, Electro-, or Photocatalysis

Direct conversion of earth-abundant methane into value-added chemicals under mild conditions is an attractive technology in response to the increasing industrial demand of feedstocks and worldwide appeal of energy conservation. Exploring advanced low-temperature C–H activation catalysts and reaction systems is the key to converting methane in a direct and mild manner. The recently developed reaction processes operated at low-temperature thermocatalysis systems or driven in electro- and photocatalysis systems shine light on the way to achieve efficient methane conversion with much economical energy input. In this review, we summarize the typical catalytic processes employed in these reaction systems and in particular highlight the potential heterogeneous catalysts with noteworthy C–H activation performance. We also present the progress along with our perspectives on catalyst design, theoretical simulations, the choice of reaction condition, and the method of reaction product analysis to encourage more viable technology for low-temperature methane conversion in the future.