Dual gas-diffusion membrane- and mediatorless dihydrogen/air-breathing biofuel cell operating at room temperature

• Published in: Journal of power sources Vol. 335; pp. 105 - 112
• Main Authors: Xia, Hong-qi, So, Keisei, Kitazumi, Yuki, Shirai, Osamu, Nishikawa, Koji, Higuchi, Yoshiki, Kano, Kenji
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.12.2016
• Subjects: Bioelectrocatalysis; Biofuel cell; Direct electron transfer; Gas-diffusion; Direct electron transfer; Gas-diffusion; Biofuel cell; Bioelectrocatalysis
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2016.10.030

A membraneless direct electron transfer (DET)-type dihydrogen (H2)/air-breathing biofuel cell without any mediator was constructed wherein bilirubin oxidase from Myrothecium verrucaria (BOD) and membrane-bound [NiFe] hydrogenase from Desulfovibrio vulgaris Miyazaki F (MBH) were used as biocatalysts for the cathode and the anode, respectively, and Ketjen black-modified water proof carbon paper (KB/WPCC) was used as an electrode material. The KB/WPCC surface was modified with 2-aminobenzoic acid and p-phenylenediamine, respectively, to face the positively charged electron-accepting site of BOD and the negatively charged electron-donating site of MBH to the electrode surface. A gas-diffusion system was employed for the electrodes to realize high-speed substrate supply. As result, great improvement in the current density of O2 reduction with BOD and H2 reduction with MBH were realized at negatively and postively charged surfaces, respectively. Gas diffusion system also suppressed the oxidative inactivation of MBH at high electrode potentials. Finally, based on the improved bioanode and biocathode, a dual gas-diffusion membrane- and mediatorless H2/air-breathing biofuel cell was constructed. The maximum power density reached 6.1 mW cm−2 (at 0.72 V), and the open circuit voltage was 1.12 V using 1 atm of H2 gas as a fuel at room temperature and under passive and quiescent conditions. [Display omitted] •Improvement of DET-type bioelectrocatalysis of BOD at negatively charged electrode.•Improvement of DET-type bioelectrocatalysis of MBH at postively charged electrode.•Gas-diffusion system to improve fuel supply and suppress oxidative inactivation of MBH.•H2/air-breathing biofuel cell at room temperature with a high power density.