Core-Shell Design of Metastable Phase Catalyst Enables Highly-Performance Selective Hydrogenation
Jiaqi Su1, Yujin Ji2, Shize Geng1
1College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Jiangsu, 215123, China.
Advanced Materials (Deerfield Beach, Fla.)
|October 31, 2023
Summary
This study introduces a novel metastable catalyst for selective alkyne semihydrogenation, achieving high efficiency and selectivity. The new catalyst design offers a promising alternative to expensive noble metal catalysts in the chemical industry.
Area of Science:
- Catalysis
- Materials Science
- Chemical Engineering
Background:
- Selective semihydrogenation of alkynes to alkenes is vital for the chemical industry.
- Developing non-noble metal catalysts with high activity and selectivity is a significant challenge.
- Metastable phase catalysts show potential for high activity, but selectivity control is difficult.
Purpose of the Study:
- To develop a novel metastable phase core-shell catalyst for highly selective alkyne semihydrogenation.
- To investigate the activity, selectivity, and universality of the new catalyst.
- To understand the mechanistic basis for the catalyst's performance.
Main Methods:
- Synthesis of a face-centered cubic (fcc) Ag core-metastable hexagonal closest packed (hcp) Ni shell catalyst.
- Testing the catalyst for the semihydrogenation of phenylacetylene and its derivatives.
- Conducting mechanistic investigations, including electron transfer analysis.
Main Results:
- The fcc Ag/hcp Ni core-shell catalyst demonstrated high conversion rates and selectivity for alkyne semihydrogenation.
- Achieved a high turnover frequency (TOF) of 8241.8 h⁻¹, surpassing stable phase and noble metal catalysts.
- Mechanistic studies indicated that surface oxidation of hcp Ni, due to electron transfer to the Ag core, enhances selectivity by reducing styrene adsorption.
Conclusions:
- This work presents a high-performance metastable phase catalyst for selective alkyne semihydrogenation.
- The findings are significant for designing advanced metastable catalysts with controlled selectivity.
- The developed catalyst offers a promising non-noble metal alternative for industrial applications.
More Related Videos
Related Concept Videos
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.3K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.3K
02:13Reduction of Alkenes: Catalytic Hydrogenation
12.1K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
12.1K
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
7.7K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
7.7K
01:28Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation
4.6K
Unlike the easy catalytic hydrogenation of an alkene double bond, hydrogenation of a benzene double bond under similar reaction conditions does not take place easily. For example, in the reduction of stilbene, the benzene ring remains unaffected while the alkene bond gets reduced. Hydrogenation of an alkene double bond is exothermic and a favorable process. In contrast, to hydrogenate the first unsaturated bond of benzene, an energy input is needed; that is, the process is endothermic. This is...
4.6K
02:50Catalysis
27.0K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
27.0K
02:17Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule
14.3K
If a set of reactants can yield multiple constitutional isomers, but one of the isomers is obtained as the major product, the reaction is said to be regioselective. In such reactions, bond formation or breaking is favored at one reaction site over others.
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
14.3K