Univ Sao Paulo, Dept Quim, Fac Filosofia Ciencias & Letras Ribeirao Preto, BR-14040901 Ribeirao Preto, SP - Brazil
 Univ Utah, Dept Chem, Salt Lake City, UT 84112 - USA
 Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 - USA
Total Affiliations: 3
Journal of Power Sources;
JUL 1 2015.
Web of Science Citations:
Recently, there has been much effort in developing metal nanoparticle catalysts for fuel oxidation, as well as the development of enzymatic bioelectrocatalysts for fuel oxidation. However, there has been little study of the synergy of hybrid electrocatalytic systems. We report the preparation of hybrid bioanodes based on Au nanoparticles supported on multi-walled carbon nanotubes (MWCNTs) co-immobilized with glucose oxidase (GOx). Mediated electron transfer was achieved by two strategies: ferrocene entrapped within polypyrrole and a ferrocene-modified linear poly(ethylenimine) (Fc-LPEI) redox polymer. Electrochemical characterization of the Au nanoparticles supported on MWCNTs indicate that this catalyst exhibits an electrocatalytic response for glucose even in acidic conditions. Using the redox polymer Fc-LPEI as the mediator, voltammetric and amperometric data demonstrated that these bioanodes can efficiently achieve mediated electron transfer and also indicated higher catalytic currents with the hybrid bioelectrode. From the amperometry, the maximum current density (J(max)) achieved with the hybrid bioelectrode was 615 +/- 39 mu A cm(-2), whereas the bioanode employing GOx only achieved a J(max) of 409 +/- 26 mu A cm(-2). Biofuel cell tests are consistent with the electrochemical characterization, thus confirming that the addition of the metallic species into the bioanode structure can improve fuel oxidation and consequently, improve the power generated by the system. (C) 2015 Elsevier B.V. All rights reserved. (AU)