Fabrication of Vertically aligned Copper Nanotubes as a Novel Electrode for Enzymatic Biofuel Cells

Herein, Laccase catalysed oxygen reduction reaction on polyaniline coated copper nanotube bio-cathode was studied. The copper nanotubes were grown in anodic aluminium oxide template on which conductive polymer polyaniline was electrodeposited. Laccase was covalently immobilized using a linker molecule glutraldehyde. The effective wiring of enzyme with bio-cathode was confirmed by linear sweep voltammetry, chronoamperometry and open circuit potential measurement. All electro analysis was performed in conventional three electrode system using platinum wire counter electrode and Ag/AgCl reference electrode. The bio-cathode in air saturated phosphate buffer showed maximum OCP and current of 0.59 V and 140.12 μAcm−2 respectively. Moreover, electrochemical impedance analysis confirmed decrease in charge transfer resistance with the immobilization of enzyme on CuNTs/polyaniline electrode. The bio-cathode showed reproducibility and stability over the period of examination.