Wang Wenzhong, research team of Shanghai Institute of silicate, Chinese Academy of Sciences, has made new progress in the study of photocatalytic conversion of methane

Methane, as the main component of natural gas and shale gas, has the advantages of relatively rich reserves and low price It is one of the core research and development in the field of replacing oil to produce liquid fuel and basic chemicals The oxygen-containing derivatives of methane, especially the alcohol derivatives, are considered as the backbone of carbon chemistry Methane is the most stable organic small molecule, but after the activation of C-H bond, it can get high active intermediate species, which is prone to over activation and complete mineralization Because of its broad prospects and great challenges, the selective activation and directed conversion of methane is a worldwide problem, known as the "Holy Grail" in the field of catalysis and even chemistry Up to now, the indirect method is usually used to convert methane into syngas through steam reforming at high temperature, and then obtain multi carbon basic chemicals through Fischer Tropsch synthesis, or prepare methanol from syngas and produce other chemicals The conversion route is lengthy, energy consumption is high, and a large amount of greenhouse gas carbon dioxide is emitted in the process, which not only brings environmental load, but also makes the utilization rate of total carbon less than half Therefore, scientists have been trying to explore the method of direct conversion and utilization of methane Photocatalytic direct conversion can break the shackles of traditional thermodynamic equilibrium and make the conversion of methane at low temperature and atmospheric pressure Recently, the research team of Wang Wenzhong from Shanghai Silicate Research Institute of Chinese Academy of Sciences has made new progress in the study of photocatalytic conversion of methane The team designed and prepared copper modified carbon nitride materials to realize the direct conversion of methane to ethanol, and carried out a more in-depth study on the catalytic mechanism The related research results were published in nature communications (DOI: 10.1038 / s41467-019-08454-0) under the title of "direct functionality of metal into ethanol over copermodified polymer carbon nitride via photocatalysis", and applied for a Chinese invention patent (201811339733.2) The first author was Zhou Yuanyi, doctoral student of Shanghai Silicate Institute In view of the problem that methane is prone to over activation and complete mineralization, from the two perspectives of the generation of active oxygen species and the adsorption and activation of methane, the research team not only realized the in-situ formation of hydroxyl radicals, but also promoted the C-H of methane by modifying copper in the orderly cavity of carbon nitride materials The activation of bonds and the stabilization of highly active intermediate species The material shows excellent photocatalytic performance for methane conversion, and the yield of ethanol is the best value reported in related fields In addition to the free radical mechanism, there is a synergistic effect between the copper species in the material and the adjacent carbon atoms, which makes the conversion process along the path of methane methanol ethanol This work proposes a new strategy of direct conversion of methane to liquid fuel under mild conditions, which is helpful to deepen the understanding of the formation mechanism of multi carbon products Relevant research work has been supported by NSFC.