Novel Flower-like PdAu(Cu) Anchoring on a 3D rGO-CNT Sandwich-stacked Framework for Highly Efficient Methanol and Ethanol Electro-oxidation

By integrating three beneficial considerations (alloying effect, surface compositional modulation and supporting aspect), a series of 3-dimensional (3D) rGO-CNT supported activated electrocatalysts have been prepared by electrochemical Cu depletion from as-prepared PdAuCu/rGO-CNTs catalysts. The as-prepared and activated catalysts were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). The results show that, on one hand, the Cu content in PdAuCu/rGO-CNTs greatly affects the electrochemical feature and surface topography of the following activated counterpart; on the other hand, the activated PdAuCu(50%)/rGO-CNTs with typical flower-like topography exhibits excellent electrocatalytic activity as high as 1046.72 and 2347.97 mA mg−1 Pd for methanol and ethanol oxidation in alkaline solution, revealing the highest activity improvement compared with the other ones. The catalytic activity enhancement causation based upon the electrochemical activation induced unique structural and functional properties of different component in the nanocatalyst and the synergistic effect between them was also discussed in this article.