Abstract:
A novel microwave-assisted intercalation (MAI) strategy is proposed for fast and efficient intercalation of layered MXene to prepare large-size single-layer MXene. After LiF-HCl etching of Ti3AlC2, the as-prepared multi-layer Ti3C2Tx (M-T) are intercalated with Li3AlF6 as an intercalator and ethylene glycol (EG) as a solvent under microwave irradiation for 5 min. Furthermore, the dispersed high-quality large-sized single-layer Ti3C2Tx (S-T) nanosheets with a thickness of 1.66 nm and a large lateral size over 20 µm are achieved with a yield of over 60% after a further ultrasonic delamination followed by electrostatic precipitation, acid washing, and calcination. In addition, Pd/S-T composite catalyst, which is constructed with Pd nanoparticles supported on the as-prepared S-T nanosheets, exhibits an excellent performance for rapid and efficient selective hydrogenation of nitroarenes with H2 under a mild condition. At room temperature, full conversion of nitrobenzene and 100% aniline selectivity are achieved over Pd/S-T catalyst in 20 min with 0.5 MPa of H2 pressure. This work provides a novel method for facile, fast, and large-scale preparation of single-layer MXene and develops a new approach for constructing efficient nanocatalytic systems.
摘要:
提出了一种新型的微波辅助插层(MAI)策略,用于快速有效地嵌入层状MXene,以制备大尺寸的单层MXene。在对Ti3AlC2进行LiF-HCl蚀刻后,将制备的多层Ti3C2Tx(M-T)与作为嵌入剂的Li3AlF6和作为溶剂的乙二醇(EG)在微波辐射下嵌入5分钟。此外,分散的高质量大尺寸单层Ti3C2Tx(S-T)纳米片的厚度为1.66nm,横向尺寸超过20μm,在进一步超声分层后,其产量超过60%静电沉淀,酸洗,和煅烧。此外,Pd/S-T复合催化剂,它是由Pd纳米颗粒负载在制备的S-T纳米片上构成的,在温和条件下用H2快速有效地选择性氢化硝基芳烃具有优异的性能。在室温下,在0.5MPa的H2压力下,在Pd/S-T催化剂上在20分钟内实现了硝基苯的完全转化和100%的苯胺选择性。这项工作提供了一种新的方法,快,和大规模制备单层MXene,并开发了一种构建高效纳米催化体系的新方法。