Abstract
We describe complete lactate electrooxidation in an enzymatic biofuel cell that combines the catalytic action of the bimetallic composite Ru@Pt-CNT and the enzyme oxalate oxidase (OxOx). The Ru@Pt-CNT/OxOx hybrid electrode was 2.0-fold more catalytically active than the electrode containing the bimetallic composite only. During chronoamperometric experiments, the hybrid electrode achieved a 35% higher maximum current density (2.65 ± 0.15 mA cm-2) than the Ru@Pt-CNT electrode. Electrochemical impedance spectroscopy showed that the hybrid electrode had lower charge transfer resistance than the Ru@Pt-CNT electrode, confirming that OxOx had a high affinity for lactate during the bioelectrocatalytic reaction on the electrode surface. Furthermore, 18-h long-term bulk electrolysis revealed that lactate electrooxidation at the Ru@Pt-CNT/OxOx hybrid electrode provided a total charge of 1.2 ± 0.2 C, which was 3-fold higher than the total charge generated by the Ru@Pt-CNT electrode. The lactate oxidation products generated at the hybrid electrode were detected during bulk electrolysis by chromatography, which showed that the hybrid biofilm harvested all 10 electrons from lactate, completely oxidizing it to CO2. With exceptional stability and catalytic performance, the hybrid electrode acted in the multiple catabolic steps of lactate oxidation. Overall, the interaction between Ru@Pt-CNT and OxOx enhanced the assembly of lactate biofuel cells to improve lactate electrooxidation. This could pave the way for developing efficient electronic devices with promising applications in bioelectrochemistry.
Recommended Citation
J. H. Franco et al., "Enhanced Biofuel Cells Based On A Hybrid Enzymatic/Bimetallic Composite For Complete Lactate Catalytic Electrooxidation," ACS Materials Au, American Chemical Society, Jan 2025.
The definitive version is available at https://doi.org/10.1021/acsmaterialsau.5c00039
Department(s)
Chemistry
Publication Status
Open Access
Keywords and Phrases
energy generation; enzymatic biofuel cell; lactate oxidation; metallic catalyst; oxalate oxidase
International Standard Serial Number (ISSN)
2694-2461
Document Type
Article - Journal
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2025 American Chemical Society, All rights reserved.
Creative Commons Licensing
This work is licensed under a Creative Commons Attribution 4.0 License.
Publication Date
01 Jan 2025
Comments
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Grant 00x0ma614