Electrospun carbon fibers: a promising electrode material for abiotic and enzymatic catalysis in hybrid biofuel cell
Résumé
In the present international crisis of fossil energy, renewable energies and biofuel cells (BFCs) emerge as interesting sustainable sources for greatly limiting environmental impact and having a strong growth in market share. In this context, we are developing a prototype of hybrid biofuel cells able to convert chemical energy to electrical energy from abiotic oxidation of carbohydrates on metallic nanoparticle catalysts, combined with enzymatic reduction of O2 to H2O by bilirubin oxidase (BOD). The advantage of the hybrid biofuel cell is on one hand, the selectivity of the enzyme toward the electrochemical reduction of O2, and on other hand, fast reaction kinetics of carbohydrate oxidation and long-term stability thanks to metallic nanoparticle catalysts. Based on strategies related to the fabrication of new and active electrodes with high specific area, we have synthesized novel carbon nanofibers-based electrodes by electrospinning [1] to increase enzyme loadings and facilitate electron transfer between the enzyme and the electrode substrate. This work presents the electroactivity of different compositions of nanometallic anode catalysts (Au, Pt, Pd) synthesized by Bromide Anion Exchange [2] toward the carbohydrate oxidation. Furthermore, the performance of the device made with these anode materials associated with the optimized electrode/enzyme assembly is discussed. With a glucose concentration of 10 mM, a power density of 90 μW cm-2 is delivered at 0.37 V. [1] Nanotechnology 24, 2013, 245402. [2] Electrocatalysis 2 (4), 2011, 268.