Pt–NiO/C anode electrocatalysts for direct methanol fuel cells

Pt catalyst was supported on Vulcan XC-72R containing 5 wt.% NiO using NaBH4 as a reducing agent. The prepared catalyst was heat-treated at 400 °C. XRD, TEM and EDX analyses were applied to characterize Pt–NiO/C electrocatalyst. The introduction of NiO reduces the particle size of Pt crystallites. The electrocatalytic activity of Pt–NiO/C electrocatalysts was examined towards methanol oxidation reaction in 0.5 M H2SO4 solution using cyclic voltammetry and chronoamperometry techniques. A three fold increment in the oxidation current density was gained at Pt–NiO/C electrocatalyst compared to Pt/C one. The corresponding chronoamperograms showed high steady state current density values suggesting better stability of Pt–NiO/C electrocatalyst towards the carbonaceous poisoning species. The enhanced electrocatalytic performance and the long-term cycle durability of Pt–NiO/C electrocatalyst are attributed to the strong interaction between Pt and NiO and the formation of small Pt crystals.