Immobilized glucose oxidase biofuel cell anode by MWCNTs, ferrocene, and polyethylenimine: Electrochemical performance

Abstract

Ferrocene-functionalized polyethylenimine and multiwalled carbon nanotubes were attached covalently by glutaraldehyde onto a carbon cloth to develop an immobilized enzyme (glucose oxidase) electrode for biofuel cell applications. Developed enzymatic anode was characterized by electrochemical methods to determine electrochemical performance. Anodic open-circuit potential was measured as within 0-20 mV range. Cyclic voltammetry showed anodic peak for glucose oxidation around 400-600 mV (vs. sat. Ag/AgCl) varying with scan rate. An enzyme fuel cell with 2.5 mg/cm 2 glucose oxidase-loaded bioanode and 0.70 mg/cm 2 Pt-loaded cathode attached to Nafion™ 115 membrane has provided around 2.5 mA/cm 2 current density at short-circuit conditions. Enzymatic kinetic parameters of prepared anode were determined by electrochemical methods that surprisingly indicated less K M (i.e., better substrate affinity) than that of determined by conventional enzymatic methods. Enzymatic stability determined by electrochemical methods moreover indicated longer enzyme half-life.

Performance Assessment of a Perfluorosulfonic Acid‐type Membrane (i. e. Nafion™ 115) for an Enzymatic Fuel Cell

“…Preparation of glucose oxidase immobilized bioanode was described previously . Typically; 4 g dry BPEI was dissolved in 45 mL methanol (MetOH).…”

“…0.4 g FcCHO in 5 ml methanol was added slowly into the BPEI solution at 25 °C. The mixture was stirred at 100 rpm for 24 h for the reaction and the product was stabilized by adding NaBH 4 . 0.5 ml of 40 mg ml −1 Fc−BPEI including Fc−BPEI−MetOH solution was added onto a carbon cloth, which was previously treated with 10 mg MWCNTs (dry basis), for the adsorption of Fc−BPEI by MWCNTs.…”

“…In this study, a high power enzymatic fuel‐cell was developed by using a recently developed glucose oxidase (GOx) immobilized bio‐anode . A popular high performance 125 μ‐thick perfluorosulfonic acid‐type proton exchange membrane (i. e. Nafion® 115) and a conventional platinum−carbon based cathode were used for the integration of the biofuel‐cell.…”

Development of Reasonably Stable Chitosan Based Proton Exchange Membranes for a Glucose Oxidase Based Enzymatic Biofuel Cell

“…In our previous studies, the immobilized GOx bio‐anode having relatively high current density underperformed when it was integrated with the popular perfluorosulfonic acid‐type membrane (i. e. Nafion® 115). A fast current density performance decay (from 2.13 mA cm −2 to 0.28 mA cm −2 within 2 hours) was observed and this behavior was explained by perfluorosulfonic acid‐type membranes proton transport mechanism that was inhibited by the other cations if they are in the reaction medium .…”

“…Therefore, many studies were performed for enzyme electrode development to increase performance [35][36][37][38][39][40][41][42][43]. One the other hand, one of the important challenges for the enzymatic biofuel cell applications is membrane development for proton transfer since popular fuel cell membranes (i. e. perfluorosulfonic acid type membranes like Nafion ® ) are found as not effective because of cation inhibition [6,[18][19]. It was observed clearly from Figure 9 that chitosan membranes could be an effective proton transfer membrane alternative for enzymatic biofuel cells.…”