Dual gas-diffusion membrane- and mediatorless dihydrogen/air-breathing biofuel cell operating at room temperature

Abstract

A membraneless direct electron transfer (DET)-type dihydrogen (H2)/air-breathing biofuel cell without any mediator was constructed wherein bilirubin oxidase from Myrothecium verrucaria (BOD) and membrane-bound [NiFe] hydrogenase from Desulfovibrio vulgaris Miyazaki F (MBH) were used as biocatalysts for the cathode and the anode, respectively, and Ketjen black-modified water proof carbon paper (KB/WPCC) was used as an electrode material. The KB/WPCC surface was modified with 2-aminobenzoic acid and p-phenylenediamine, respectively, to face the positively charged electron-accepting site of BOD and the negatively charged electron-donating site of MBH to the electrode surface. A gas-diffusion system was employed for the electrodes to realize high-speed substrate supply. As result, great improvement in the current density of O2 reduction with BOD and H2 reduction with MBH were realized at negatively and postively charged surfaces, repectively. Gas diffusion system also supressed the oxidative inactivation of MBH at high electrode potentials. Finally, based on the impoved bioanode and biocathode, a dual gas-diffusion membrane-and mediatorless H2/air-breathing biofuel cell was constructed. The maximum power density reached 6.1 mW cm −2 (at 0.72 V), and the open circuit voltage was 1.12 V using 1 atm of H2 gas as a fuel at room temperature and under passive and quiescent conditions.

Direct Electron Transfer-type Bioelectrocatalysis of Peroxidase at Mesoporous Carbon Electrodes and Its Application for Glucose Determination Based on Bienzyme System

“…16,17 It has been proposed that mesoporous structures with porous radii close to the radius of an enzyme [18][19][20] and electrostatic interaction between the redox center of an enzyme and an electrode surface [21][22][23][24][25][26] are important to improve the performance of DET-type bioelectrocatalysis. Therefore, there seems to be some possibility to construct mesoporous electrodes suitable for DET reaction of POD.…”

An Air‐breathing Carbon Cloth‐based Screen‐printed Electrode for Applications in Enzymatic Biofuel Cells

“…For the modification of the prototype gas‐breathing SPEs with bilirubin oxidase from Myrothecium verrucaria ( Mv ‐BOx) the electrodes were first chemically modified with 2‐amino benzoic acid (2‐ABA) by oxidation of the amino group in 2‐ABA accompanied with binding of this intermediate to the carbon surface using an electrochemical grafting process . 2‐ABA grafting was performed before mounting the carbon cloth to the SPE substrate.…”

“…Modification with the enzyme was achieved by means of a drop cast process. The 2‐ABA modifier ensures an oriented immobilization and a productive wiring of the enzyme in a direct electron transfer regime .…”

“…Modification of the gas breathing SPEs with the biocatalyst Mv ‐BOx was performed following a protocol reported previously . In brief, the working electrode was first modified with 2‐ABA using a one‐step electrochemical grafting process.…”

Fructose Dehydrogenase Electron Transfer Pathway in Bioelectrocatalytic Reactions

“…The electrochemistry of redox proteins has been actively studied to establish this electron transfer mechanism due to its envisioned advantages in applications in bioelectrochemical devices, such as biosensors [9] and biological fuel cells. [10] D-fructose dehydrogenase is an oxidoreductase which catalyses the oxidation of D-fructose to keto-D-fructose. It contains 3 subunits: subunit I (67 kDa), which contains flavin adenine dinucleotide (FAD), where the catalytic process takes place; subunit II (51 kDa) with three heme c moieties acting as the redox prosthetic groups; [11] and subunit III (20 kDa), which has no cofactors, but most probably plays a significant role in maintaining the stability of the molecule.…”