Preparation Of Surpportless Copper-Baced Alloy Nanotubes And Their Electrocatalitic Properties

A galvanic replacement route was developed for preparing Cu-Pd alloy nanotube electrocatalysts with different composition by using cheap Cu nanowires (NWs) as sacrificial templates. The experimental conditions was researched, including the type and concentration of the precursor palladium saltthe and reaction temperature. We have studied the effect of law, properties of the alloy composition and crystal structure for electrical catalyzed. The findings provide new insights into the synergistic catalytic activity for the design of surpoortless electrocatalysts.Firstly, the Cu-Pd nanotubes are approximately 100 nm in diameter and several micrometers long. The wall thickness of the Cu-Pd nanotubes is 20 nm. The Cu45Pd55 catalyst exhibited the best ORR performance and the largest exchange current density, which is remarkably higher than that of the commercial Pt/C (E-TEK). XPS measurements demonstrated that the unique electronic structures of the catalysts are associated with the compositions. The origin of the ORR activity may be substantially related to an optimum Pt 4f binding energy that dominates the best catalytic activity toward ORR. The Cu45Pd55 nanotubes exhibits enhanced electro-catalytic activity and improved resistance to CO poisoning during methanol electrooxidation, compared to a commercial Pt/C (E-TEK). The main reason for its enhanced activity is that the addition of copper makes palladium lose electronics, which promoted C-H bond rupture and promote the formation of a large amount of Pd-OHad to accelerate oxidation intermediate products, thereby improving the catalytic activity and resistance to CO poisoning.Secondly, by adding CuCl complexing agent Na2S2O3, it proved that in displacement reaction, the reaction path is generated cuprous chloride. Cuprous disproportionation occurred, decomposition of Cu and Cu2+. Kirkendall effect leads to a hollow tubular structure.Finally, By adding sodium thiosulfate as an additive, using galvanic replacement method, we prepared copper-based amorphous alloy nanotubes. The copper-based amorphous nanotubes are approximately 100 nm in diameter and several micrometers long. The wall thickness of the copper-based amorphous nanotubes is 15 nm. The Cu-Pt amorphous nanotubes exhibits enhanced electro-catalytic activity and improved resistance to CO poisoning during methanol electrooxidation, compared to a commercial Pt/C (E-TEK). Its activity is enhanced because promoting adsorption and activation of methanol. Then Pt-OHad generation is promoted, to accelerate oxidation of Pt-COad, and ultimately thereby improving the catalytic activity and resistance to CO poisoning.