Defect‐Engineered Ruthenium MOFs as Versatile Heterogeneous Hydrogenation Catalysts

Abstract

Ruthenium MOF [Ru3(BTC)2Yy] ⋅ Gg (BTC=benzene‐1,3,5‐tricarboxylate; Y=counter ions=Cl−, OH−, OAc−; G=guest molecules=HOAc, H2O) is modified via a mixed‐linker approach, using mixtures of BTC and pyridine‐3,5‐dicarboxylate (PYDC) linkers, triggering structural defects at the distinct Ru2 paddlewheel (PW) nodes. This defect‐engineering leads to enhanced catalytic properties due to the formation of partially reduced Ru2‐nodes. Application of a hydrogen pre‐treatment protocol to the Ru−MOFs, leads to a further boost in catalytic activity. We study the benefits of (1) defect engineering and (2) hydrogen pre‐treatment on the catalytic activity of Ru−MOFs in the Meerwein‐Ponndorf‐Verley reaction and the isomerization of allylic alcohols to saturated ketones. Simple solvent washing could not avoid catalyst deactivation during recycling for the latter reaction, while hydrogen treatment prior to each catalytic run proved to facilitate materials recyclability with constant activity over five runs.

Synthesis, characterization and application of defective metal–organic frameworks: current status and perspectives

“…The mixedlinker approach can increase the number of defect sites or active sites by incorporating another linker with various unique functionalities. 34,[60][61][62][63] By using this mixed-linker approach, Epp et al 61 successfully introduced point defects at the distinct Ru 2 paddlewheel nodes in ruthenium MOF Ru-HKUST-1. Mixtures of benzene-1,3,5-tricarboxylate and pyridine-3,5-dicarboxylate linkers were used in the mixed-linker approach.…”

TiO2@UiO‐66 Composites with Efficient Adsorption and Photocatalytic Oxidation of VOCs: Investigation of Synergistic Effects and Reaction Mechanism

“…[17] Based on these characteristics, MOFs have attracted great study in many fields, such as gas storage, [18] separation [19] and catalysis. [20] Meanwhile, MOFs have been used in photocatalytic oxidation of VOCs as photocatalysts and exhibit some photocatalytic activity. [21][22][23] TiO 2 À UiO-66-NH 2 composite was synthesized and used for VOCs degradation under flowing conditions.…”

“…MOFs have drawn extensive attention due to the tunable pore size, large surface area, pore volumes and designable framework structures [17] . Based on these characteristics, MOFs have attracted great study in many fields, such as gas storage, [18] separation [19] and catalysis [20] . Meanwhile, MOFs have been used in photocatalytic oxidation of VOCs as photocatalysts and exhibit some photocatalytic activity [21–23] .…”

Defect Engineering of Carbon‐based Electrocatalysts for Rechargeable Zinc‐air Batteries

“…[23][24] Defect engineering of carbons, such as the modification of the electronic structure and surface chemical state of the carbon skeleton, is an effective strategy to further improve their electrochemical performance. [25][26][27][28] To be specific, intrinsic carbon defects can be directly used as effective active sites. However, their combination with heteroatom dopant/metal species, they can be also used to construct other effective synergistic active sites.…”

“…Carbon nanomaterials, including 0D (e. g., fullerene), 1D (e. g., carbon nanotubes (CNTs)), 2D (e. g., graphene) and 3D porous carbon nanostructures, have been widely reported [23–24] . Defect engineering of carbons, such as the modification of the electronic structure and surface chemical state of the carbon skeleton, is an effective strategy to further improve their electrochemical performance [25–28] . To be specific, intrinsic carbon defects can be directly used as effective active sites.…”