INVESTIGADORES
FLEXER Victoria
congresos y reuniones científicas
Título:
Three-Dimensional Carbonaceous Porous Electrodes for Efficient Biofuel Cells
Autor/es:
VICTORIA FLEXER; BRUN, N.; BACKOV, R.; MANO, N.
Lugar:
Niza
Reunión:
Conferencia; 61st Annual Meeting of the International Society of Electrochemistry; 2010
Institución organizadora:
International Society of Electrochemistry
Resumen:
Today,
low current densities produced by biofuel cells are one of the main challenges
to address to present them as a plausible alternative to primary batteries. In
such context, three dimensional electrode architectures are promising since
they would highly increase the reactive surface area and therefore the enzyme
loading, allowing for current enhancement. However, as large enzyme loading
means larger substrate consumption, electrode materials should be designed to
allow both for large surface area and fast mass transport of fuel
simultaneously.
Based
on these premises, carbonaceous electrodes with interconnected hierarchical
porosity were synthesized through coating a tetrahydrofuran (THF)
solution of preformed formophenolic resin into a Si(HIPE), a silica macroporous framework,[1] and were further modified to
prepare both mediated and non-mediated enzyme electrodes. We will show that these
electrodes are promising candidates as electrode materials for the elaboration
of efficient biofuel cells and biosensors, producing higher and more stable currents
than flat electrodes. The preparation protocol is simple and low cost. The
mechanical strength and the synthetic route allow for the external shape and
size of the electrodes to be designed on demand, which is a most important
feature to incorporate these electrodes into devices.
In
the first example, we will show results for the modification of the carbonaceous
foams with a redox hydrogel made of glucose oxidase (GOx) and an electron
conducting Os-polymer. The glucose electrooxidation current was 13-fold higher
than on a flat glassy carbon electrode modified with the same mass loading of
bioelectrocatalyst. In a second example, the carbonaceous foams were modified
with Bilirubin Oxidase (BOD). The direct electron transfer reduction signal
started at 0.45V (vs Ag/AgCl) and reached 2 mA cm-2 at 0V, at pH =
7.2, 37oC, and under O2.