Structural and morphological characterization of gold–nickel electrocatalyst synthesized by taking advantage of the AuNi phase separation mechanism

The Au–Ni bimetal nanoparticles were prepared by coreduction in aqueous solution and post-heat-treatment process. In this synthesis approach, NaBH4 was used as reductive reagent and sodium dodecyl sulfate was added as surfactant to control the size and the morphology of the nanoparticles. Post-heat-treatment was performed to further remove the oxide species on the surface of the nanoparticles. Structural and compositional evolution analysis of the nanostructured bimetals are performed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectrometry (XPS) measurements. The Au–Ni electrocatalysts for electro-oxidation of formic acid in acidic media were investigated.