Fabrication of high performance carbon-supported ternary Pd-Cu-Fe electrocatalysts for formic acid electrooxidation via partly galvanic sacrifice of tunable binary Cu-Fe alloy templates

Carbon loaded Pd-Cu-Fe catalysts (Pd-Cu-Fe/C) were fabricated with a novel strategy of partly etching carbon loaded tunable binary Cu-Fe alloy templates (Cu9Fe1, Cu8Fe2, Cu7Fe3) with Pd2+. The obtained Pd-Cu-Fe catalysts started from all the three templates showed better performance for formic acid oxidation than Pd and Pt. Compared with Pd/C catalysts, the anodic peak potential at the catalysts started from Cu9Fe1, Cu8Fe2 and Cu7Fe3 shifted toward negative value by 51 mV, 88 mV and 110 mV, respectively. Among them, catalyst started from Cu7Fe3 template exhibited the highest catalytic activity and a high stability, suggesting that it is a good candidate for the formic acid fuel cell. The characteristics of the Pd-Cu-Fe/C ternary catalysts were correlated using X-ray diffraction analysis, X-ray photoelectron spectroscopy, inductively coupled plasma-atomic emission spectrometry, energy dispersive spectrometer, transmission electron microscopy, and electrochemical measurements.