Electrodeposition of thin sulfide films:: nucleation and growth observed for Bi2S3

The potentiostatic pulse technique proved to be the most powerful electrochemical technique for in situ studies of the early stages of Bi2S3 electrodeposition on bismuth. The current-time response recorded at the overpotentials in the vicinity of E-r (Bi2S3/Bi) in dependence of hydrogen sulfide ion concentrations, was described by a theoretical expression for three-dimensional progressive nucleation and growth under diffusion control. Through the application of relations which hold true for such a nucleation model, the following parameters were determined: (i) the anodic nucleation potential (E-AN); (ii) the rate of nucleation (AN(infinity)); (iii) the diffusion coefficient (D); and (iv) the density of the growing sites (N-s). (C) 2002 Elsevier Science B.V. All rights reserved.