A novel three-dimensional carbonized PANI1600@CNTs network for enhanced enzymatic biofuel cell

•A novel 3D composite of PANI1600@CNTs is prepared by in-situ polymerization and then carbonized at 1600 °C.•The carbonized PANI on the CNTs surface presents the rhizobium-like structure.•The carbonized PANI acts like conductive “glue” and connects the adjacent tubes together.•Three of the fabricated EBFCs in series are able to lightening up a yellow LED whose turn-on voltage is ~1.8 V.

A novel three-dimensional (3D) carbon composite of PANI1600@CNTs with rhizobium-like structure is prepared by in-situ polymerization of aniline monomers around and along the functionalized carbon nanotubes (CNTs) and then carbonized at 1600 °C for enzymatic biofuel cells (EBFCs). The SEM and TEM images clearly show that the carbonized PANI grew seamlessly on the surface of CNTs and presented the rhizobium-like structure. The carbonized PANI acts like conductive “glue” and connects the adjacent tubes together, which can assemble the CNTs into a 3D network. The PANI1600@CNTs composite modified glassy carbon electrodes based on glucose oxidase (GOx) and laccase (Lac) exhibit high electrochemical performance. A glucose//O2 EBFC constitutes of the fabricated anode and cathode performs a maximum power density of 1.12 mW cm−2 at 0.45 V. Furthermore, three of the fabricated EBFCs in series are able to lightening up a yellow light-emitting diode (LED) whose turn-on voltage is about at 1.8 V. This work may be helpful for exploiting novel substrates by carbonizing the composites of conducting polymer with nano materials at high-temperature for immobilization of enzymes in the EBFCs or biosensor fields.