Biocathodes for Enzymatic Biofuel Cells Using Laccase and Different Redox Mediators Entrapped in Polypyrrole Matrix

Abstract

This paper describes a comparative study of laccase-based biocathodes containing different redox mediator species, namely porphyrin, ferrocene, osmium, and ruthenium complexes were immobilized onto carbon platforms entrapped in an electropolymerized polypyrrole matrix. Ferrocenium hexafluorophosphate (Fc), an Iron (III) porphyrin (FeTMPyP), a ruthenium complex [Ru(byp) 2 Cl 2 ], and an osmium complex [Os(byp) 2 Cl 2 ] were employed as redox mediators and have been characterized by cyclic voltammetry. Methanol/O 2 biofuel cell tests employing the biocathodes showed that they provide higher output power as compared with other systems. In the best conditions, the maximum power densities reached values around 81 ± 4 and 71 ± 3 μW cm −2 for [Ru(bpy) 2 Cl 2 ] and [Os(bpy) 2 Cl 2 ] at pH 4.5, respectively.

Anthraquinone and L-amino Acid Derivatives Schiff Base Cu(II) Complexes as a Mediator between Cathode of Biofuel Cell and Oxygen-reducing Laccase

“…This is called the mediator (MET) type enzyme function electrode reaction, can be adapted to most of the oxidation-reduction enzyme system, the selection of the mediator, modification methods must be important [12][13][14][15][16].…”

Ru(II)-diimine functionalized metalloproteins: From electron transfer studies to light-driven biocatalysis

“…[75] In biofuel cells, laccases have been immobilized on carbon based polypyrrole film where various embedded Ru(II) and Os(II) complexes act as redox mediators to create biocathodes. [76, 77] Such redox hydrogel design has led to efficient dioxygen electroreduction outperforming platinum-based catalysts. [76-78]…”

“…[76, 77] Such redox hydrogel design has led to efficient dioxygen electroreduction outperforming platinum-based catalysts. [76-78]…”

Membraneless ethanol,O2 enzymatic biofuel cell based on laccase and ADH/NAD+ bioelectrodes

“…The osmium [Os(bpy)2Cl2] and ruthenium complex [Ru(bpy)2Cl2] catalysts for laccase biocathode was synthesized according to the literature 22,23 15 . To this end, 50 L of a stock solution, prepared by mixing laccase (300 L; 3.32 mg mL -1 ), PAMAM dendrimer (100 L; 0.025 mol L -1 ), and acetate buffer solution (ABS; 200 L; 100 mmol L -1 ; pH 4), was deposited on the previously modified carbon platform.…”

“…Several methodologies can be employed to obtain polyPYR layers, and use of this polymer, modified or not, has been often reported [12][13][14] . Our research group prepared enzymatic biocathode and bioanode for biofuel cells 15,16 , and an example of MlessEBFCs application can be found elsewhere 17 . PolyPYR and MWCNT matrixes have been employed to prepare glucose,O2 EBFCs based on glucose oxidase (GOx) and pyrroloquinoline quinone (PQQ) redox mediator absorbed on MWCNTs and polyPYR as a MWCNTs-GOx-PQQ-polyPYR bioanode 17 .…”