Electrocatalytic Aromatic Alcohols Splitting to Aldehydes and H2 Gas
Zhao Zhang1, Bing-Liang Leng1, Shi-Nan Zhang1
1School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformation Molecules, Shanghai Jiao Tong University, Shanghai 200240, PR China.
Journal of the American Chemical Society
|September 19, 2024
Summary
This study introduces a novel alcohol splitting reaction (ASR) for efficient aldehyde and hydrogen production. This method avoids side reactions, achieving high selectivity and durability in electrocatalysis.
Area of Science:
- Electrocatalysis
- Green Chemistry
- Materials Science
Background:
- Traditional alcohol oxidation reactions (AORs) suffer from low selectivity and efficiency due to competing water oxidation.
- Active oxygen species in aqueous electrolytes lead to unwanted side reactions and decreased product yield.
Purpose of the Study:
- To develop an electrocatalytic system for selective alcohol to aldehyde transformation.
- To enable simultaneous production of fine chemicals (aldehydes) and pure hydrogen gas.
- To overcome the limitations of conventional AORs by preventing competitive reactions.
Main Methods:
- Development of an integrated all-solid proton generator-transfer electrolyzer.
- Utilizing platinum (Pt) nanoparticles as a proton generator to cleave only O-H and C-H bonds.
- Employing a 3D conducting network of ionomers and carbon spheres for proton transport.
Main Results:
- Achieved >99% selectivity for aldehydes by completely avoiding oxygen active species reactions.
- Demonstrated continuous operation for at least 10 days at a low cell voltage of 1.2 V.
- Obtained high Faradaic efficiency of 80-93% for aldehyde production, significantly outperforming conventional AORs (<22% selectivity, <3 h durability).
Conclusions:
- The developed alcohol splitting reaction (ASR) offers a highly selective and efficient pathway for aldehyde and hydrogen co-production.
- The all-solid proton generator-transfer electrolyzer design effectively prevents competitive reactions, enhancing overall process performance.
- This approach represents a significant advancement in electrocatalytic alcohol transformation for sustainable chemical synthesis.
Related Concept Videos
01:17Electrophilic Aromatic Substitution: Friedel–Crafts Alkylation of Benzene
6.4K
Friedel–Crafts reactions were developed in 1877 by the French chemist Charles Friedel and the American chemist James Crafts. Friedel–Crafts alkylation refers to the replacement of an aromatic proton with an alkyl group via electrophilic aromatic substitution. A Lewis acid catalyst such as aluminum chloride reacts with an alkyl halide to form a carbocation. The resulting carbocation then reacts with the aromatic ring and undergoes a series of electron rearrangements before giving the...
6.4K
02:35Acid-Catalyzed Dehydration of Alcohols to Alkenes
19.3K
In a dehydration reaction, a hydroxyl group in an alcohol is eliminated along with the hydrogen from an adjacent carbon. Here, the products are an alkene and a molecule of water. Dehydration of alcohols is generally achieved by heating in the presence of an acid catalyst. While the dehydration of primary alcohols requires high temperatures and acid concentrations, secondary and tertiary alcohols can lose a water molecule under relatively mild conditions.
19.3K
01:19Aldehydes and Ketones with Alcohols: Hemiacetal Formation
5.9K
Similar to water, alcohols can add to the carbonyl carbon of the aldehydes and ketones. The addition of one molecule of alcohol to the carbonyl compound forms the hemiacetal or half acetal. As depicted below, in a hemiacetal, the carbon is directly linked to an OH and OR group.
5.9K
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
02:13Reduction of Alkenes: Catalytic Hydrogenation
11.9K
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...
11.9K
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.2K
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...
3.2K