The development of superior non-platinum electrocatalysts for enhancing the electrocatalytic activity and stability for the oxygen-reduction reaction (ORR) and liquid fuel oxidation reaction is very important for the commercialization of fuel cells,but still agreat challenge.Herein, we demonstrate an ew colloidal chemistry techniquef or making structurally ordered PdCu-based nanoparticles (NPs) with composition control from PdCu to PdCuNi and PtCuCo.U nder the dual tuning on the composition and intermetallic phase,the ordered PdCuCo NPs exhibit better activity and muche nhanced stability for ORR and ethanol-oxidation reaction (EOR) than those of disordered PdCuM NPs,t he commercial Pt/C and Pd/C catalysts.T he density functional theory (DFT) calculations reveal that the improved ORR activity on the PdCuM NPs stems from the catalytically active hollows ites arising from the ligand effect and the compressive strain on the Pd surface owingtothe smaller atomic sizeofCu, Co,and Ni.