Pulse-electrodeposition of PtNi nanoparticles on a novel substrate of multi-walled carbon nanotubes/poly(eriochrome blue-black B) as an active and durable catalyst for the electrocatalytic oxidation of methanol

Abstract

• A facile producer is developed for deposition of Pt-Ni nanoparticles by improving the size, dispersion, and promoting the catalyst utilization on a polymeric substrate. • Electropolymerization of eriochrome blue-black B is reported for the first time. • The pulsed electrodeposition of the metal ions has more catalytic properties with higher current density and lower onset potential than chronoamprometric method. • PtNi@p-EBB is an effective electrocatalyst with long-time stability for methanol oxidation in alkaline media. Herein, a simple and novel methodology for fabricating a high-methanol-tolerant electrocatalyst based on poly(eriochrome blue-black B)/multi-walled carbon nanotubes, coated with nickel and platinum nanoparticles is described. The polymer thin film was prepared using cyclic voltammetry and pulsed electrodeposition technique was used to decorate the polymer layer with nickel and platinum nanoparticles. The energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM), and inductively coupled plasma analyses were performed to characterize the prepared catalyst. The morphological studies reveal that the PtNi-nanoparticles were distributed without accumulation throughout the polymer layer. The development of pulse electrodeposition technique for immobilization of PtNi-nanoparticles on the polymeric substrate significantly improves the size, dispersion, and promotes the catalyst utilization. The PtNi@p-EBB/MWNT catalyst show high stability and high current density (1550 mA.mg -1 Pt).