Water-repellent-treated enzymatic electrode for passive air-breathing biocathodic reduction of oxygen

• Published in: Electrochemistry communications Vol. 36; pp. 46 - 49
• Main Authors: Nakagawa, Takaaki, Mita, Hiroki, Kumita, Hideyuki, Sakai, Hideki, Tokita, Yuichi, Tsujimura, Seiya
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.11.2013; Amsterdam Elsevier; New York, NY
• Subjects: Applied sciences; Bilirubin oxidase; Biocathode; Biofuel cell; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Ferricyanide; Fuel cells; Oxygen reduction; Water repellent; Oxygen reduction; Ferricyanide; Biocathode; Biofuel cell; Bilirubin oxidase; Water repellent; Oxygen; Enzyme; Cathode; Lysine polymer; Polyaminoacid; Electrode material; Enzyme electrode; Electrodes; Chemical reduction; Redox couple; Biochemical fuel cell; Preparation; Air breathing fuel cell; Hexacyanoferrates III; Oxidoreductases
• ISSN: 1388-2481; 1873-1902
• DOI: 10.1016/j.elecom.2013.09.012

A passive-type air-breathing biocathode using bilirubin oxidase as enzyme, ferricyanide as redox mediator, and poly-l-lysine as linker was investigated. Water-repellents from Scotchgard™ with dissolved in methyl isobutyl ketone were directly applied to the enzyme- and mediator-modified biocathode. The partially water-repelled biocathode was placed on a gas-permeable polytetrafluoroethylene (PTFE) membrane and immersed in a buffer solution, and O2 was passively supplied to the biocathode through the PTFE membrane from air. Cathodic currents were dependent on the buffer concentration and amount of applied water repellent. Steady-state catalytic current densities reached 24 and 32mAcm−2 at 0V vs. Ag|AgCl under air and oxygen atmospheric conditions, respectively, using a biocathode modified with 0.32mgcm−2 of the water repellent and 2.0M imidazole buffer at pH7. •Oxygen reduction current reached 20mAcm−2 at 0.25V vs. Ag|AgCl sat. at pH7.•Oxygen is passively supplied to the biocathode through the PTFE film from air.•Water-repellents were directly applied to the biocathode.