Optimized electrode arrangement and activation of bioelectrodes activity by carbon nanoparticles for efficient ethanol microfluidic biofuel cells

• Published in: Journal of power sources Vol. 269; pp. 834 - 840
• Main Authors: SELLOUM, D, TINGRY, S, TECHER, V, RENAUD, L, INNOCENT, C, ZOUAOUI, A
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier 10-12-2014
• Subjects: Applied sciences; Carbon; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Electrodes; Energy; Energy. Thermal use of fuels; Engineering Sciences; Enzymes; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Ethanol; Ethyl alcohol; Exact sciences and technology; Fuel cells; Fuels; Materials; Micro and nanotechnologies; Microelectronics; Microfluidics; Nanoparticles; Optics; Photonic; Fluid mechanics; Ethanol; Enzyme; Nanoparticle; Precision engineering; Alcohol; Activation; Carbon; Optimization; Electrodes; Biochemical fuel cell; Carbon nanoparticles; Microequipment; Enzymatic biofuel cell; Kinetics; Miniaturization; Bioelectrodes; Enzyme kinetics; Microfluidics
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2014.07.052

This work presents the construction of an ethanol microfluidic biofuel cell based on a biocathode and a bioanode, and operating in a Y-shaped microfluidic channel. At the anode, ethanol was oxidized by alcohol dehydrogenase, whereas at the cathode, the oxygen was reduced by laccase. Fuel and oxidant streams moved in parallel laminar flow without turbulent mixing into a microchannel fabricated using soft lithography methods. The enzymes were immobilized in the presence of reactive species at gold electrode surfaces. Bioelectrocatalytic processes were enhanced by combination of enzymes and carbon nanoparticles, attributed to appropriate electron transport and high amount enzyme loading. The benefit of the nanoparticles with higher surface porosity was explained by the high porous structure that offered a closer proximity to the reactive species and improved diffusion of the substrates within the enzyme films. The microfluidic BFC was optimized as function of electrode patterns, showing that higher current and power densities were achieved for shorter and wider electrodes that allow for thinner boundary layer depletion at the electrodes surface resulting in efficient catalytic consumption of fuel and oxidant. This miniaturized device generated maximum power density of 90 [mu]W cm super(-2) at 0.6 V for a flow rate 16 [mu]L min super(-1).