Plasmon-mediated electrocatalysis based on plasmonic gold nanoparticles (Au NPs) has emerged as a promising approach to facilitate electrochemical reactions with the introduction of light to excite the plasmonic electrodes. We have investigated the electrochemical oxidation of 4-(hydroxymethyl)benzoic acid (4-HMBA) on gold (Au), nickel (Ni), and platinum (Pt) metal working electrodes in alkaline electrolytes. Au has the lowest onset potential for catalyzing the electrooxidation of 4-HMBA among the three metals in base, whereas Pt does not catalyze the electrooxidation of 4-HMBA under alkaline conditions, although it is conventionally a good electrocatalyst for alcohol oxidation. Both 4-carboxybenzaldehyde and terephthalic acid are detected as the products of electrochemical oxidation of 4-HMBA on the Au working electrode by high-performance liquid chromatography . The electrodeposited Au NPs on indium tin oxide (ITO)-coated glass is further utilized as the working electrode for the 4-HMBA electrooxidation. With its broad absorption in the visible and near-infrared range, we show that the Au NPs on the ITO electrode could enhance the electrochemical oxidation of 4-HMBA under green and red LED light illuminations (505 and 625 nm). A possible reaction mechanism is proposed for the electrochemical oxidation of 4-HMBA on Au working electrodes in an alkaline electrolyte.
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Electrocatalytic synthesis of heterocycles from biomass-derived furfuryl alcohols
Abstract It is very attractive yet underexplored to synthesize heterocyclic moieties pertaining to biologically active molecules from biomass-based starting compounds. Herein, we report an electrocatalytic Achmatowicz reaction for the synthesis of hydropyranones from furfuryl alcohols, which can be readily produced from biomass-derived and industrially available furfural. Taking advantage of photo-induced polymerization of a bipyridyl ligand, we demonstrate the facile preparation of a heterogenized nickel electrocatalyst, which effectively drives the Achmatowicz reaction electrochemically. A suite of characterization techniques and density functional theory computations were performed to aid the understanding of the reaction mechanism. It is rationalized that the unsaturated coordination sphere of nickel sites in our electrocatalyst plays an important role at low applied potential, not only allowing the intimate interaction between the nickel center and furfuryl alcohol but also enabling the transfer of hydroxide from nickel to the bound furfuryl alcohol.
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- Award ID(s):
- 1914546
- NSF-PAR ID:
- 10309519
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41467-021-22157-5
