Chembio-Energy

The project Chembio-Energy concerns the development of processes for chemical-to-energy transformation of renewable and clean resources issued from biomass. More precisely, it concerns the construction of a sustainable biofuel cell (BFC) device capable of converting chemical energy to electrical energy by abiotic transformation of carbohydrates combined with enzymatic reduction of O2 to H2O without hydrogen peroxide as intermediate. The advantages of our approach lie in the design of an ecological prototype of hybrid biofuel cell that uses carbohydrates (glucose, sucrose or lactose, ...) as renewable, biodegradable and bio-sourced fuels from biomass that present a maximum guarantee of security and non toxicity. In this sustainable biofuel cell, the reactions will be the oxidation of the carbohydrate on Au-Pt catalyst as anode and the dioxygen reduction to water catalyzed by the enzyme bilirubin oxidase as cathode. The number of hybrid BFCs, based on nanoparticles as catalysts for glucose oxidation, is an emerging field, only restricted to a few recent devices. Compared to existing biofuel cells working with two enzymatic catalysts at the anode and the cathode, the advantage of the hybrid biofuel cell is on one hand, the selectivity of the enzyme towards the electrochemical reduction of O2, and on other hand, fast reaction kinetics of carbohydrate oxidation and long-term stability thanks to metallic nanoparticle catalysts. Various bimetallic catalysts compositions will be tested by electrochemistry to define the most efficient composition to activate glucose oxidation. In the present proposal, we address two issues by presenting a complete manufacturing device that will deliver high power output (500 and 1000 µW cm-2) with an improved durability. An important point of these investigations concerns the use of the most efficient electrode materials for optimizing the proposed biofuel cell prototype. Based on novel strategies related to the synthesis of new electrodes with increased specific surface, we will synthesize novel carbon nanofibers-based electrodess with high electrical conductivity to increase enzyme loadings and facilitate electron transfer between enzymes and electrodes. Besides, because most of the biofuel cells are limited by the turn-over rate of their bioelectrocatalysts, our strategy will be to design high turnover rate of the enzyme bilirubin oxidase (BOD) by purification technique and by random or directed mutagenesis of the enzyme. All these issues will be addressed simultaneously based on the synergy of the different partners.