Monocarboxylic acid etching strategy: Modulation of chemical environment of Ni nanoparticles in defective Ce-UiO-66 to construct heterogeneous interfaces for dicyclopentadiene hydrogenation

Abstract

The hierarchical porous and chemical microenvironmental properties of Metal-Organic Frameworks (MOFs) have been emphasized in catalytic applications. In this work, after selectively removing ligands from frameworks of Ce-UiO-66 by monocarboxylic acid etching, they exhibit obvious mesoporous properties with essentially unchanged crystallinity. Distinguishing from other pore-making methods, the MOFs have abundant missing sites after etching, and Ni nanoparticles (NPs) can be efficiently anchored in the framework of defective Ce-UiO-66, resulting in the formation of Ce-O-Ni heterogeneous interfaces. The chemical environments of Ni NPs can be modulated through the Ce-O-Ni interfaces, and the metal-support interaction improves the charge densities between the active sites. The prepared catalysts showed high conversion and selectivity in the hydrogenation reaction of dicyclopentadiene, and also had good cycling performance. The present work provides new insights into the construction of hierarchical porous defective MOFs with abundant heterogeneous interfaces for hydrogenation reactions.