Abstract
A nanoporous gold (NPG) electrode prepared through a facile anodization technique was employed in the electrochemical reductive amination of biomass-derivable α-keto acids in the presence of a nitrogen source to produce the corresponding amino acids. NPG showed a clear reductive current in the presence of α-keto acid and NH2OH, and the electrolysis experiments confirmed the production of L-amino acid. A reductive voltammetric signal at the NPG electrode appeared at a more positive potential by 0.18–0.79 V, compared with those at the planar-gold electrode without anodization and other previously reported electrode systems, indicating the high activity of the prepared nanostructure for the electrochemical reaction. Maximum Faradaic efficiencies (FEs) of 74–93% in the reductive molecular conversion to amino acids of Ala, Asp, Glu, Gly, and Leu were obtained under the optimized conditions. The FE values were strongly dependent on the applied potential in the electrolysis, suggesting that the hydrogen evolution reaction at the electrode surface was more significant as the applied potential became more negative. The effect of potential at the NPG was lower than that at the planar-gold electrode. These results indicate that nanostructurization decreases the overpotential for the electrochemical reductive amination, resulting in high FE.
Highlights
As the demand for a sustainable society increases, efforts have been made to develop environmentally friendly methods for chemical production [1]
The reductive current signal of HER against the total reductive signal at the planar-gold electrode was larger than that at the Nanoporous gold (NPG) electrode. These voltammetric features are consistent with the effect of the applied potential on the Faradaic efficiencies (FEs) in L-glutamic acid production. These results suggest that nanostructurization of the surface of the planargold electrode by the facile anodization process improves the activity for the reduction of α-keto glutaric acid than for HER
The anodized NPG surface was employed for the electrochemical molecular conversion of biomass-derivable α-keto acids in the presence of a nitrogen source to the corresponding L-amino acids
Summary
As the demand for a sustainable society increases, efforts have been made to develop environmentally friendly methods for chemical production [1]. The NPG surface exhibited the reductive current starting at around 0.1 V, which was a much more positive potential by 0.18–0.30 V compared with those at the planar-gold (Figure 2e) and previously reported TiO2 electrodes (with a scan rate of 10 mV s−1 and pH 0.53) [33] with NH2OH as the nitrogen source. Ppoloteynetdia. lPsointetnhteiarlessiunltths ewreerseucltosnwveerrteecdotnovtehreterdevtoertshieblreehveyrdsriobgleehnyedlercotgreonde el(eRcHtrEod) ere(fReHreEn)cere[f3e3r]e.nVceol[t3a3m].mVeotlrtyamwmasetpryerwfoarsmpeedrffoorrmthede pfoortethnetipalorteanntgieasl roafn−g0e.s3otof −0.05.3V, tode0p.5eVn,ddinegpeonndtihnegeoxnpethriemeexnptearlicmonendtiatilocnosnadtiptiootnesnatitapl soctaenntriaatlesscoanf 5r–a5te0smoVf 5s–−51.0 mV s−1
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
