A high-performance glucose/oxygen biofuel cell based on multi-walled carbon nanotube films with electrophoretic deposition

Abstract

Electrode supports play a significant role in the assembly of high-performance biofuel cells (BFCs) since they connect the active center of biocatalysts and the charge collectors directly. In this manuscript, novel nanostructured multi-walled carbon nanotube (MWCNT) films were fabricated by electrophoretic deposition (EPD-MWCNT films) as electrode supports for high-performance BFCs. Flavin adenine dinucleotide-dependent glucose dehydrogenase and laccase were modified on EPD-MWCNT films to fabricate the bioanodes and biocathodes, respectively, with Os-complexes as mediators. For comparison, drop-casted MWCNT films or buckypapers have been prepared and adopted for the construction of BFCs with the same biocatalysts. EPD-MWCNT films which have vegetable sponge-like networks should be the optimal electrode supports for glucose/O2 BFCs with higher power density. The EPD-MWCNT films based glucose/O2 BFC showed a high maximum power density of 0.43 ± 0.03 mW cm−2 and open circuit voltage of 0.59 V, which is significantly superior to those values of the BFCs based on drop-cast MWCNT films or buckypapers, contributing to the electrode supports of EPD-MWCNT films with vegetable sponge-like nanostructure. Moreover, the BFC retained 56% of its original power density even after continuous operation for 7 days. Our findings would open an avenue for the development of more efficient BFCs with EPD-MWCNT films as the electrode supports.