Graphene-supported Pd–Pt alloy nanoflowers: In situ growth and their enhanced electrocatalysis towards methanol oxidation

• In situ growth of Pd–Pt alloy nanoflowers on reduced graphene oxide is developed.
• One-pot polyallylamine hydrochloride-assisted co–chemical reduction is applied.
• The supported hybrid nanocatalysts exhibit enhanced performance for methanol oxidation.
• Proposed protocol gives insight to design of in situ growth of supported catalysts.

In situ growth of Pd–Pt alloy nanoflowers on host reduced graphene oxide (Pd–Pt ANFs/RGO) nanosheets by one–pot polyallylamine hydrochloride-assisted co–chemical reduction method, is developed. Compared with the common approaches to assembly of nanocatalysts in selected substrates based on pre-synthesized catalyst nanoparticles, the in situ fabrication is more facile, cost-effective and environment-friendly, allowing effective control of the location, distribution and uniformity of the supported Pd–Pt nanoflowers through the entire matrix. The detailed morphology, composition and structure of Pd–Pt ANFs/RGO nanocomposites are investigated by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), selected-area electron diffraction (SAED), energy dispersive spectrum (EDS), and nitrogen adsorption–desorption isotherms (SADI). TEM images show that Pd–Pt ANFs are directly grown on RGO with porous structure and good dispersion. Against commercial Pd/C catalyst, Pd–Pt ANFs/RGO nanocomposites show superior electrocatalytic activity, stability and satisfactory CO tolerance towards methanol oxidation reaction in basic electrolyte.

Evenly-spread porous Pd–Pt alloy nanoflowers on reduced graphene oxide nanosheets, in situ grown by one-pot polyallylamine hydrochloride-assisted co–chemical reduction method, display markedly enhanced electrocatalytic activity for methanol oxidation towards DMFCs applications.Figure optionsDownload as PowerPoint slide