A high-performance bioanode based on a nitrogen-doped short tubular carbon loaded Au nanoparticle co-immobilized mediator and glucose oxidase for glucose/O2 biofuel cells

Abstract

A high performance bioanode based on a nitrogen-doped short tubular carbon (N-STC) loaded Au nanoparticle (Au NP) co-immobilized mediator and glucose oxidase (GOD) was developed for glucose/O₂ biofuel cells (BFCs). Ferrocenecarboxaldehyde (Fc), as the mediator, was covalently linked with L-cysteine (CYS) and then immobilized on the surface of Au NP modified N-STCs through the Au–S bond to obtain Fc-CYS-Au/N-STC hybrids. GOD was then immobilized on the surface of the hybrids with glutaraldehyde (GA) crosslinking. The resulting GOD/Fc-CYS-Au/N-STC modified glassy carbon (GC) electrode exhibited good catalytic activity towards glucose oxidation and excellent stability. For the assembled glucose/O₂ BFC with the GOD/Fc-CYS-Au/N-STC electrode as the bioanode and a commercial E-TEK Pt/C modified GC electrode as the cathode, the open circuit potential is 0.71 V and the maximum power density of 83.6 μW cm⁻² can be achieved at 0.21 V.