Carbon nanotubes coated with platinum nanoparticles as anode of biofuel cell

A hybrid system of carbon nanotubes (CNTs) coated with poly (amidoamine) (PAMAM) dendrimerencapsulated platinum nanoparticles (Pt-DENs) and glucose oxidase (GOx) was prepared through the layer-by-layer (LbL) self-assembly approach and then used as anode in enzyme-based biofuel cells (BFCs).The assembly process was monitored by ζ-potential measurement,and the as-resulted Pt-DENs/CNTs nanocomposites were characterized by transmission electron microscopy (TEM).The performance of electrodes modified by Pt-DENs/CNTs was also investigated by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV).We found that the Pt-DENs/CNTs could enhance the electron transfer between the redox centers in enzyme and the electrode surfaces.Furthermore,by employing the Pt-DENs/CNTs modified electrodes as anode,the enzyme-based BFCs operated in a solution containing glucose generated an open-circuit voltage of approximately 640.0 mV and a maximum current density of about 90.0 μA/cm2,suggesting that Pt-DENs/CNTs may serve as an alternative anode to previously used noble metals in BFC applications.