Viscosity Effects in Thin-Layer Electrodeposition
- 1 January 2001
- journal article
- Published by The Electrochemical Society in Journal of the Electrochemical Society
- Vol. 148 (7), C479-C487
- https://doi.org/10.1149/1.1377280
Abstract
We present experimental results and a theoretical macroscopic model on the effects of viscosity in thin-layer electrochemical growth. The viscosity was changed through glycerol additions; simultaneous use was made of optical and schlieren techniques for tracking concentration and convective fronts, while pH indicators were used for migratory fronts. The theoretical model describes diffusive, migratory, and convective ion transport in a fluid subject to an electric field. The equations are written in terms of dimensionless quantities, in particular, the Migration, Peclet, Poisson, Reynolds, and electrical Grashof numbers, which are found to depend on viscosity. Experiments reveal that with increasing viscosity, convection decreases, concentration profiles are less pronounced, while electric resistance and voltage increase. Concentration and convective fronts slow down with viscosity, but their time scaling follows the same law as for solutions without glycerol, only differing by a constant. Moreover, under constant electrical current, an increase in viscosity yields slower deposit front velocities, a more uniform deposit with smaller separation between branches, i.e., a change in morphology from more separated compact trees to a more dense, fractal-like structure. © 2001 The Electrochemical Society. All rights reserved.Keywords
This publication has 40 references indexed in Scilit:
- Growth model for ramified electrochemical deposition in the presenceof diffusion, migration, and electroconvectionPhysical Review E, 1997
- Interferometric characterization of growth dynamics during dendritic electrodeposition of zincPhysical Review E, 1996
- Growth pattern formation in copper electrodeposition: Experiments and computational modellingChaos, Solitons, and Fractals, 1995
- A macroscopic model for growth pattern formation of ramified copper electrodepositsChaos, Solitons, and Fractals, 1995
- The Role of Induced Convection in Branched Electrodeposit Morphology SelectionJournal of the Electrochemical Society, 1994
- experimental evidence for gravity induced motion in the vicinity of ramified electrodepositsElectrochimica Acta, 1994
- Recent Progress in Electrochemical Deposition without Supporting ElectrolyteMRS Proceedings, 1994
- Growth of three-dimensional silver fractal electrodeposits under damped free convectionPhysical Review E, 1993
- Coupling of drift, diffusion, and electroconvection, in the vicinity of growing electrodepositsPhysical Review E, 1993
- Morphology Selection and the Concentration Boundary Layer in Electrochemical DepositionJournal of the Electrochemical Society, 1991