Additive-free macroscopic-scale synthesis of coral-like nickel cobalt oxides with hierarchical pores and their electrocatalytic properties for methanol oxidation

Abstract

Coral-like nickel cobalt oxides with hierarchical pores were massively synthesized via a one-pot additive-free solvent thermal decomposition route coupled with a post calcination treatment. The physicochemical properties of nickel cobalt oxides were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS) and nitrogen sorption measurements. The unique 3D hierarchical porous NiCo2O4 coral structures exhibit enhanced electrocatalytic properties for methanol oxidation with a desirable stability. The large-scale and facile additive-free synthetic technique can be applied to the construction of other metal oxide with complex hierarchical structures.