Electrochemical investigation of electrodeposited platinum nanoparticles on multi walled carbon nanotubes for methanol electro-oxidation

Abstract

Abstract: The electrodeposition of platinum nanoparticles (PtNPs) on multiwall carbon nanotubes (MWCNTs)/fluorine-doped tin oxide glass (FTO) was investigated. Nucleation and growth mechanisms were studied via Scharifker and Hills model. Chronoamperometry results clearly show that the electrodeposition processes are diffusion-controlled and the diffusion coefficient is 1.5×10-5cm2/s. The semi-spherical particles with lamellar morphology were observed in 1M H 2SO 4, while a petal shape was discerned in 0.5M H 2SO 4. Also, dispersion, size, and uniformity of PtNPs were investigated, where the finer distribution of PtNPs with the average size less than 100 nm was obtained in 0.5M H 2SO 4 solution, and the mean diameter of Pt crystals was 20 nm. Finally, the electro-oxidation of methanol and oxygen reduction studied via cyclic voltammetry showed that as-prepared PtNPs/MWCNTs electrodes had superb electrocatalytic activity. Graphical Abstract:: Electrodeposition of platinum nanoparticles (PtNPs) on multiwall carbon nanotubes (MWCNTs)/flourine-doped tin oxide glass (FTO) was conducted successfully. The electrodeposition mechanism of PtNPs nucleation and growth on MWCNTs was studied. It was found that fine and well-distributed PtNPs/MWCNTs electrode shows a high electrochemical activity for methanol electro-oxidation. [Figure not available: see fulltext.].