Comparison of the structure and methanol electrooxidation ability from irregular PtNi nanocrystals to PtNiRu nanodendrites†
In this work, platinum–nickel–ruthenium (PtNiRu) nanocrystals with different amounts of Ru were synthesized by a one-pot solvothermal method. In the absence and presence of ruthenium trichloride, the evolution of the structure and composition of the obtained Pt alloys was clearly observed. In comparison with PtNi irregular nanocrystals, PtNiRu nanospheres and nanodendrites were obtained under the same reaction conditions. The structure, composition and the formation pathway of the PtNiRu nanodendrites were investigated in detail. Finally, the catalytic results from the methanol oxidation suggested that the mass activity and the area specific activity of the PtNiRu nanodendrites were 3.5 and 3.1-fold higher than those of commercial Pt/C, as well as having better durability, which was due to the porous structure and synergistic effect of Ni/Ru. It is expected that the present study could provide a new approach for designing alloys based on Pt modified with low amounts of Ru for energy conversion applications.