CAS Key Laboratory of Nanosystem and Hierachical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P.R. China.
Nanoscale. 2018 Sep 13;10(35):16425-16430. doi: 10.1039/c8nr05801f.
Metal-organic frameworks (MOFs) have great potential to become innovative heterogeneous supports for immobilizing catalytically active noble metal nanoparticles (NPs). However, unlike metal oxide supports, the interfacial interactions between noble metal NPs and MOFs are currently neglected, thus dramatically diminishing the advantage of MOFs as supports. Herein, ZIFs(Co/Zn)@M (M = Pd, Pt or Au) nanocomposites with well-defined interfaces are synthesized and used as catalysts in gas-phase CO oxidation and liquid-phase C6H5CHO oxidation. Notably, in both reactions, ZIF-67(Co)@M samples exhibit better catalytic activity than ZIF-8(Zn)@M samples, and moreover, the catalytic activity of ZIFs@Pd is higher than that of ZIFs@Pt and ZIFs@Au samples. Experimental and theoretical results reveal that the enhanced catalytic activity originates from the interfacial electron transfer from ZIFs to noble metal NPs as well as the coupling between d band of noble metal in NPs and metal node in ZIFs.
金属-有机骨架（MOFs）在成为固定催化活性贵金属纳米粒子（NPs）的创新多相载体方面具有巨大潜力。然而，与金属氧化物载体不同，贵金属 NPs 与 MOFs 之间的界面相互作用目前被忽视，从而大大降低了 MOFs 作为载体的优势。在此，合成了具有明确界面的 ZIFs(Co/Zn)@M（M = Pd、Pt 或 Au）纳米复合材料，并将其用作气相 CO 氧化和液相 C6H5CHO 氧化的催化剂。值得注意的是，在这两种反应中，ZIF-67(Co)@M 样品的催化活性均优于 ZIF-8(Zn)@M 样品，而且，ZIFs@Pd 的催化活性高于 ZIFs@Pt 和 ZIFs@Au 样品。实验和理论结果表明，增强的催化活性源于 ZIFs 向贵金属 NPs 的界面电子转移以及 NPs 中贵金属的 d 带与 ZIFs 中金属节点之间的耦合。
