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Updated: Sep 21, 2025
10:39
Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction
Published on: August 23, 2018
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Reversing the Catalytic Selectivity of Single-Atom Ru via Support Amorphization
Junyi Du1,2, Yan Huang1, Zixiang Huang1,3
1Center of Advanced Nanocatalysis (CAN), Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, P. R. China.
JACS Au
|June 1, 2022
Summary
Phase engineering of titanium dioxide supports enables single-atom ruthenium catalysts to selectively hydrogenate nitro groups over vinyl groups by altering reactant recognition. This breakthrough enhances catalyst control in complex chemical reactions.
Area of Science:
- Catalysis
- Materials Science
- Chemical Engineering
Background:
- Single-atom catalysts (SACs) offer high selectivity due to uniform active sites.
- Controlling selective activation of specific functional groups in molecules with multiple groups remains a challenge for SACs.
Purpose of the Study:
- To investigate the effect of support phase engineering on the chemo-recognition behavior of single-atom catalysts in selective hydrogenation.
- To develop a strategy for controlling the selectivity of single-atom catalysts by manipulating the support material.
Main Methods:
- Fabrication of single-atom ruthenium on amorphous porous ultrathin TiO2 nanosheets (Ru1/a-TiO2).
- Comparison of catalytic performance and electronic properties of Ru1/a-TiO2 with its crystalline counterpart (Ru1/c-TiO2).
- Utilizing density functional theory (DFT) calculations to understand reactant adsorption and activation mechanisms.
Main Results:
- Ru1/a-TiO2 exhibited enhanced positive charge on Ru atoms compared to Ru1/c-TiO2.
- Ru1/a-TiO2 demonstrated superior selectivity for nitro group hydrogenation, while Ru1/c-TiO2 favored vinyl group hydrogenation in a competitive reaction.
- DFT calculations revealed that the amorphous TiO2 support inverts reactant adsorption configurations, leading to altered chemo-recognition.
Conclusions:
- Support phase engineering is a viable strategy to precisely control the chemo-recognition and selectivity of single-atom catalysts.
- The electronic and structural properties of the TiO2 support significantly influence the catalytic behavior of supported single-atom ruthenium.
- This work provides fundamental insights into designing advanced SACs for highly selective chemical transformations.
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