A gas breathing hydrogen/air biofuel cell comprising a redox polymer/hydrogenase-based bioanode

• Main Author: Szczesny, Julian
• Publication Date: 2018
• Other Authors: Marković, Nikola, Conzuelo, Felipe, Zacarias, Sónia, Pereira, Inês A.C., Lubitz, Wolfgang, Plumeré, Nicolas, Schuhmann, Wolfgang, Ruff, Adrian
• Format: Article
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: https://doi.org/10.1038/s41467-018-07137-6
• topic: Chemistry(all); Biochemistry, Genetics and Molecular Biology(all); Physics and Astronomy(all)

Hydrogen is one of the most promising alternatives for fossil fuels. However, the power output of hydrogen/oxygen fuel cells is often restricted by mass transport limitations of the substrate. Here, we present a dual-gas breathing H2/air biofuel cell that overcomes these limitations. The cell is equipped with a hydrogen-oxidizing redox polymer/hydrogenase gas-breathing bioanode and an oxygen-reducing bilirubin oxidase gas-breathing biocathode (operated in a direct electron transfer regime). The bioanode consists of a two layer system with a redox polymer-based adhesion layer and an active, redox polymer/hydrogenase top layer. The redox polymers protect the biocatalyst from high potentials and oxygen damage. The bioanodes show remarkable current densities of up to 8 mA cm-2. A maximum power density of 3.6 mW cm-2 at 0.7 V and an open circuit voltage of up to 1.13 V were achieved in biofuel cell tests, representing outstanding values for a device that is based on a redox polymer-based hydrogenase bioanode.