甲烷选择氧化单原子催化剂的研究进展

Research progress in single-atom catalysts for the selective oxidation ofmethane

单原子催化剂在原子利用率卓越、配位环境具有可调谐性等方面表现出独特优势.其独特的原子结构通过诱导甲烷中C–H键的静电极化显著降低活化能.稳定中间体并防止反应产物的过度氧化,加速了甲烷在温和条件下的反应速率.本文综述了近年来单原子催化剂在甲烷低温液相条件下直接选择性氧化为C1~C2含氧化合物方面的研究进展.具体讨论了不同载体(碳基材料、分子筛、金属氧化物、金属有机框架)上呈原子级分散型活性位点催化剂的设计及制备方法、活化甲烷的反应机理和载体与催化性能之间的构效关系.最后,简单讨论了各类原子级分散型催化剂在甲烷选择氧化反应中的优势与挑战,并对单原子催化剂的发展进行了展望.

Single-atom catalysts exhibit significant advantages in terms of exceptional atomic utilization and tunable coordination environments.The unique atomic structure of the material enhances the reaction rate of methane under mild conditions by inducing electrostatic polarization in C–H bonds,leading to a significant reduction in activation energy.Additionally,it stabilizes intermediates and prevents excessive oxidation of reaction products.In this review,we critically summariz the recent advancements in single-atom catalyst research for the direct selective oxidation of methane to C1–C2 oxygenates under low temperature-liquid-phase conditions.In particular,the design and preparation methods of atomically dispersed active site catalysts on different supports(carbon-based materials,molecular sieves,metal oxides,metal-organic frameworks),the reaction mechanism of activated methane,and the structure-activity relationship between the support and the catalytic performance were discussed.Finally,the advantages and challenges of various atomic-level-dispersed catalysts for the selective oxidation of methane are briefly discussed,and the development of single-atom catalysts is prospected.