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Updated: Jul 18, 2025
Synthesis and Characterization of Functionalized Metal-organic Frameworks
Published on: September 5, 2014
Photo-Induced Active Lewis Acid-Base Pairs in a Metal-Organic Framework for H2 Activation
Bryan Kit Yue Ng1, Zi-Jian Zhou2, Ting-Ting Liu2
1Department of Chemistry, University of Oxford, Oxford OX1 3QR, U.K.
Abstract:
The establishment of active sites as the frustrated Lewis pair (FLP) has recently attracted much attention ranging from homogeneous to heterogeneous systems in the field of catalysis. Their unquenched reactivity of Lewis acid and base pairs in close proximity that are unable to form stable adducts has been shown to activate small molecules such as dihydrogen heterolytically. Herein, we show that grafted Ru metal-organic framework-based catalysts prepared via N-containing linkers are rather catalytically inactive for H2 activation despite the application of elevated temperatures. However, upon light illumination, charge polarization of the anchored Ru bipyridine complex can form a transient Lewis acid-base pair, Ru+-N- via metal-to-ligand charge transfer, as confirmed by time-dependent density functional theory (TDDFT) calculations to carry out effective H2-D2 exchange. FTIR and 2-D NMR endorse the formation of such reactive intermediate(s) upon light irradiation.
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