Electrochemical Synthesis Of Cd-Ag Bimetallic Particles And The Involved Alloy Formation

RUBÉN E. AMBRUSI; G. STAIKOV; SILVANA G.GARCÍA

JOURNAL OF ELECTROANALYTICAL CHEMISTRY - (Print)

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2014

1572-6657

The formation of bimetallic Cd-Ag nanoparticles on vitreous carbon (VC) and theinvolved alloy formation have been studied by conventional electrochemical techniques andex-situ atomic force microscopy (AFM). Both metals were deposited by sequentialelectrodeposition using single potentiostatic pulses. The AFM images of Ag depositsshowed small differently sized Ag nanocrystallites uniformly distributed over the VCsubstrate.This modified substrate was immersed in an electrolyte solution containing Cd2+ions and bimetallic Cd-Ag particles were prepared by underpotential deposition (UPD) of Cd. The alloy formation phenomena observed previously during Cd UPD on massive Agelectrodes were found also in the case of Cd UPD on Ag nanoparticles. The desorptionspectra in the system Cd/Ag (nanoparticles)/VC employing different polarization times,showed three desorption peaks associated with the dissolution of the Cd OPD and UPDdeposits and an Ag-Cd alloy formed at low underpotentials, respectively. Theelectrochemical behavior of the bimetallic system was also studied applying otherpolarization routine designed for this purpose.