Abstract
Based on the Fleischmann's model of nucleation and crystal growth for electrodeposition combined with the Barradas-Bosco's adsorption-nucleation model for electrochemical phase formation, the chronoamperometry was well fitted for Pt deposition on polycrystalline Au micro disc electrodes (30 μm in diameter) in different H_(2)PtCl_(6) concentrations at different over-potentials. The initial stage of Pt deposition in dilute H_(2)PtCl_(6) could be interpreted by the model of H_(2)PtCl_(6 ) adsorption combined with instantaneous nucleation and two-dimensional cylindrical growth. The rate constant of the two-dimensional growth increased linearly with overpotential. Then the deposit grew layer by layer and the rate constant increased non-linearly with overpotential. In contrast to the situation in dilute solutions, Pt deposition in higher H_(2)PtCl_(6) concentrations was found to follow the mechanism of adsorption-instantaneous nucleation and three-dimensional cone growth.The rate constant of perpendicular growth (k_(perp)) appeared two orders of magnitude larger than that of parallel growth (k_(para))_( )and increased linearly with overpotential. However, the k_(para) increased with overpotential in S shape. Both k_(perp) or k_(para) in concentrated solutions were larger than the growth rate constant in dilute solutions.
Keywords
Electrodeposition, Nucleation and crystal growth, Electrodeposition of Pt on Au, Microelectrodes
Publication Date
2004-08-28
Online Available Date
2004-08-28
Revised Date
2004-08-28
Received Date
2004-08-28
Recommended Citation
Zhi-yong TAO, Pei-fang LIU.
Nucleation and Crystal Growth of Pt Electrodeposition on Poly Crystal Au Microdisc Electrode[J]. Journal of Electrochemistry,
2004
,
10(3): 279-286.
DOI: 10.61558/2993-074X.1575
Available at:
https://jelectrochem.xmu.edu.cn/journal/vol10/iss3/5
Included in
Engineering Science and Materials Commons, Materials Chemistry Commons, Materials Science and Engineering Commons, Physical Chemistry Commons
