Hierarchical Co3O4 decorated PPy nanocasting core-shell nanospheres as a high performance electrocatalysts for methanol oxidation

Abstract

In recent times, much attention has been paid to explore economic and highly active precious metal free electrocatalysts for energy conversion and storage systems due to the expensiveness of Pt-based catalysts. Here we developed a mesoporous core-shell like nanospheres composed of a metallic cobalt oxide core wrapped with a polypyrrole nanoshell (PPy/Co3O4) for methanol electrooxidation. The performance of the core-shell PPy/Co3O4 nanospheres as anodic catalyst material was measured in 1 M KOH electrolyte and the results obtained demonstrated that the hybrid possesses high catalytic activity in terms of current density and onset voltage. The core-shell PPy/Co3O4 delivers an oxidation current density of ∼111 mA/cm2 at 0.5 V with superior stability long run stability. The observed electrocatalytic performance of the porous PPy/Co3O4 nanospheres is attributed to the integrative effects of both Co-species and layered carbon shell and presence of exceptionally numerous mesopores. Results show evidence that the earth abundant PPy/Co3O4 provide a potential electrode material for methanol electrooxidation with a satisfactory reaction activity.