Analise swot c&a

J.

Phys. D: Appl. Phys. 24 (1991) 217-225. Prinled in the UK

Electrocrystallization and electrochemical control of crystal growth: fundamental considerations and electrodeposition of metals
Frank C Walsht and Maura E Herront

t

*

Chemistry Department, Portsmouth Polytechnic, White Swan Road, Portsmouth PO1 ZDT, UK Chemistly Department, Southampton University, Highfield, Southampton SO9

5 N H , UK

Received 17 July 1990, in final form 13 November 1990
Abstract. The fundamental steps involved in an electrochemical reaction are reviewed with respect to their role in crystallization at the electrode surface. The reaction system is seen to be sensitive to the flow environment and the nature of

the electrode surface. The electrode potential can influence many features including reaction rate, chemical and phase composition, the extent of adsorption, orientation and texture. Aspects of electrocrystallization are illustrated by considering cases of metal deposition. Particular emphasis i placed upon the s development of surface roughness and the formation o metal powders during f copper deposition from aqueous acid sulphate solutions.
1. Introduction

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The term ‘electrocrystallization’ was coined by Fischer [l] in the 1940s to describe a crystallization process in which mass transfer is accompanied by charge transfer. The early development of the subject has been summarized by Bockris and Razumney [ 2 ] . In the present paper, electrocrystallization may be broadly defined as the process (or result) of a direct or indirect electrochemical influence on crystallization. (i) A direct electrochemical influence may be exerted if the value of the electrode potential dominates the type of nucleation and the growth kinetics for electrodeposition of a metal. (ii) Electrochemical reactions may indirectly alter the local reaction environment (e.g. the pH) and hence the nature of the