▎ 摘　　要

The present study reports fabrication and characterization of glucose oxidase (GOx) immobilized reduced graphene oxide (rGO), gold nanoparticles (AuNp) and rGO/AuNp composite electrodes. The study further evaluated their electrochemical behaviors using cyclic voltammetry (CV) at different scan rates (10-150 mV/s) and different glucose concentrations (0.1-0.9 M) in phosphate buffer solution (PBS) at pH 7.4. Electron transfer rate constants (k(s)) for glucose oxidation onto these enzyme immobilized electrodes have been calculated from the plot of E-p vs. log v (peak potential vs. log of scan rate) which showed faster electron transfer rate onto rGO/AuNp composite surface compared to AuNp or rGO sur-faces alone. A laboratory model enzymatic fuel cell (EFC) was constructed by coupling the anode with a potassium ferrocyanide-ferricyanide cathode under argon atmosphere. From the discharge studies, the rGO/AuNp/GOx/C-felt electrode was found to be better than AuNp/GOx/C-felt or rGO/GOx/C-felt electrodes. This better performance in rGO/AuNp/GOx/C-felt electrode has been related to the enhanced attachment of GOx enzyme onto AuNp surface through "S" atoms of sulfur containing amino acids and better electronic conductivity of rGO surface. Hence, the current study concluded that the rGO/AuNp/GOx/C-felt electrode is a promising electrode for glucose oxidation in EFCs.