Surface Review and Letters, Vol. 15, No. 6 (2008) 717–725 c  World Scientific Publishing Company NUCLEATION, GROWTH, AND MORPHOLOGICAL PROPERTIES OF ELECTRODEPOSITED NICKEL FILMS FROM DIFFERENT BATHS A. SAHARI ∗,‡ , A. AZIZI ∗ , G. SCHMERBER † and A. DINIA † ∗ Laboratoire d’Energ´ etique et d’Electrochimie du Solide, Universit´ e de S´ etif, 19000 Alg´ erie, Algeria † Institut de Physique et Chimie des Mat´ eriaux de Strasbourg, UMR 7504 du CNRS-ULP-ECPM, 23 rue du Loess, B. P. 43, 67034 Strasbourg Cedex 2, France ‡ sahariali2000@yahoo.com Received 13 June 2008 The processes of nickel electrodeposition on Pt/Si(100) substrate from an aqueous sulfate, Watts, and chloride solution have been studied using electrochemical techniques and atomic force microscopy (AFM). It was found that hydrogen evolution reaction (HER) was shifted more cathodically and the nickel electrodeposition obeys to inhibition process, caused by adsorbed species in surface substrate. At early stage of the deposition chronoamperometric results were compared with Sharifker and Hills theoretical model. The nucleation was in agreement with progressive mode followed by 3D diffusion growth mechanism. The nucleation is generally slow at low over potentials, in all studied baths. AFM images show distribution nickel clusters, with different sizes. Keywords : Deposition; diffusion; atomic force microscopy; growth. 1. Introduction Most of electroplating is a common electrochemical method, which improves the surface of various mate- rials. The improvement relies on the formation of single or multilayer coatings on the surface of met- als. Nickel electrodeposits are important industrial materials that find applications in many diverse pro- duction activities such as manufacturing of alkaline batteries, anti-corrosion paints, catalysts, and mag- netic storage media. 1-3 Therefore, it is of consid- erable interest to investigate the mechanism of the nucleation and crystal growth of nickel deposit in circumstances where the influence of the hydrogen evolution reaction (HER) is minimal, for example, by change of the electrolyte bath composition or by use of a substrate where the HER occurs at very negative potentials. It is well known, for long time, that the final morphology and texture of nickel elec- trodeposits depend greatly on solution composition, temperature, electrode potential, or current den- sity applied. 4,5 Moreover, in the three-dimensional growth initial stages of electrodeposition, the elec- trolyte nature plays an important role and may influence the growth morphology and the structure of deposits. Although a significant role is attributed to the nature of the anions of electrolyte, 6,7 their effect is still essentially obscure. To obtain a uniform electrodeposits with required quality, several baths with different compositions have been used. Among them the Watts bath, with or without additives, has been most widely used and studied. Experimen- tally it was found to be the most suitable bath for the ‡ Corresponding author. 717