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Silver particles with a novel dentrite-like structure were electrodeposited on Ti substrates from a supporting electrolyte-free 30 mmol L-1 Ag(NH3)2+ solution,to synthesize the den-Ag/Ti electrode.Binary AgxCoy/Ti electrodes with different Ag:Co atomic ratios were further obtained by electrodeposition of Co particles on the den-Ag/Ti electrode.Polyaniline (PANI) modified den-Ag/Ti and AgxCoy/Ti electrodes,PANI(n)-den-Ag/Ti and PANI(n)-AgxCoy/Ti,were finally obtained by various cyclic sweeping times (n) of aniline in Acidic and alkaline solutions,respectively.All these prepared electrodes exhibit high electroactivity for oxygen reduction reaction (ORR) in alkaline solution and their electroactivities follow the order: PANI(15)-Ag31Co69/Ti > Ag31Co69/Ti > PANI(20)-den-Ag/Ti > den-Ag/Ti.Among them,PANI(15)-Ag31Co69/Ti displays highest electroactalytic activity for ORR wit a much positive onset potential of 0 V (vs Ag,AgCl) and a high ORR current density of 1.2 mA cm-2 at -0.12 V (vs Ag,AgCl).The prepared electrocatalysts are insensitive to methanol and ethanol,and,as cathode electrocatalysts of direct alcohol fuel cells,can resist poisoning by the possible alcohol crossover from the anode.