Evaluation of alcohol dehydrogenase and aldehyde dehydrogenase enzymes as bi-enzymatic anodes in a membraneless ethanol microfluidic fuel cell

[摘要] Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (AldH) enzymes were immobilized by covalent binding and used as the anode in a bi-enzymatic membraneless ethanol hybrid microfluidic fuel cell. The purpose of using both enzymes was to optimize the ethanol electro-oxidation reaction (EOR) by using ADH toward its direct oxidation and AldH for the oxidation of aldehydes as by-products of the EOR. For this reason, three enzymatic bioanode configurations were evaluated according with the location of enzymes: combined, vertical and horizontally separated. In the combined configuration, a current density of 16.3 mA cm-2, a voltage of 1.14 V and a power density of 7.02 mW cm-2were obtained. When enzymes were separately placed in a horizontal and vertical position the ocp drops to 0.94 V and to 0.68 V, respectively. The current density also falls to values of 13.63 and 5.05 mA cm-2. The decrease of cell performance of bioanodes with separated enzymes compared with the combined bioanode was of 31.7% and 86.87% for the horizontal and the vertical array.

[发布机构] Facultad de Ingeniería, División de Investigación y Posgrado, Universidad Autónoma de Querétaro, Querétaro, Qro.; C.P. 76010, Mexico^1;Centro de Investigación y Desarrollo Tecnológico en Electroquímica, Unidad Tijuana, Tijuana; C.P. 22444, Mexico^2;Centro de Investigación y Desarrollo Tecnológico en Electroquímica, Pedro-Escobedo-Qro.; C.P. 76703, Mexico^3

[效力级别] 能源学

[关键词] Alcohol dehydrogenase;Aldehyde dehydrogenase;Combined configuration;Covalent binding;Direct oxidation;Ethanol electro-oxidation;Microfluidic fuel cell;Vertical positions