离子液体微乳液法合成Co-MOFs及其在甲苯催化氧化中应用

Preparation of Co-MOFs by Ionic Liquid Microemulsion and Their Application in Catalytic Oxidation of Toluene

室温条件下,在四元W/O型离子液体微乳液体系中制备了3种Co-MOFs纳米晶体并进行了详细的表征。为提高有机配体在水中的溶解度,选择DMF作为添加剂,从而保证Co-MOFs晶体在极性核中生长。通过调节离子液体与表面活性剂(TX-100)的质量比,有效地控制了样品的形貌和尺寸,并利用分子动力学模拟验证了该微乳体系对晶体形貌和尺寸控制的机理。同时,评价了该材料在甲苯选择性氧化反应中的催化性能。当离子液体与TX-100的质量比为1.5时,获得了由平均尺寸约为140 nm的纳米片聚集而成的晶体。该样品在甲苯氧化中表现出最佳的催化性能,其中甲苯转化率为14.5%,苯甲醛选择性为94.9%。

Three Co-MOF nanocrystals were prepared in a quaternary W/O microemulsion system at room temperature and characterized in detail.DMF was selected as additive to improve the dissolution of organic linker in water droplets and ensure the formation of Co-MOF crystals in polar core.The morphology and size of Co-MOFs were successfully controlled by adjusting the mass ratio of ionic liquid and TX-100.The mechanism of crystal growth in the microemulsion system was confirmed by molecular dynamic simulation.Meanwhile,the catalytic performance of these samples was investigated in selective oxidation reaction of toluene.When the mass ratio of ionic liquid and TX-100 was 1.5,the aggregated crystal was obtained which cumulated by nanoplate with an average size of approximately 140 nm.This sample exhibited the best catalytic performance in toluene oxidation with 14.5%toluene conversion and 94.9%benzaldehyde selectivity.