Open AccessInvestigation of Calix[4]arene Molecule on Electroless Ni-P Alloy on Carbon Steel Substrate and Evaluation of its Corrosion Resistance in 3% NaCl
Author(s) -
N. M'hanni,
M. Galai,
T. Anik,
M. Ebn Touhami,
El Housseine Rifi,
Zouhair Asfari
Publication year - 2020
Publication title -
asian journal of chemistry/asian journal of chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.145
H-Index - 34
eISSN - 0975-427X
pISSN - 0970-7077
DOI - 10.14233/ajchem.2020.22579
Subject(s) - sodium hypophosphite , chemistry , nickel , microstructure , corrosion , alloy , indentation hardness , hypophosphite , deposition (geology) , coating , nuclear chemistry , carbon steel , metallurgy , inorganic chemistry , organic chemistry , crystallography , materials science , electroplating , paleontology , layer (electronics) , sediment , biology
The autocatalytic nickel bath uses sodium hypophosphite as a reducing agent, sodium citrate as acomplexing agent and sodium acetate as an accelerator. The effect of calix[4]arene molecule type H4Lnamed (dicarboxylic acid p-tert-butylcalix[4]arene) was studied and used at various concentrations of10-3 to 10-6 M to improve the microstructure, the microhadness and properties of nickel deposit obtained.The effect of varying the concentration of H4L, on the deposition rate, the composition, themicrostructure and morphology of chemical deposition was studied. The results showed that dependingon the concentration of calix[4]arene, the deposition rate decreases from 11, to 7.75 μm/h. Themicrostructure and microhardness improves significantly at a concentration of 10-6 M of additive. Itwas also shown that the coating obtained is adherent and compact and the chemical bath has becomemore stable in the presence of calix[4]arenic additives. Indeed, in both cases, the nickel content decreasedwith the addition of concentration. This decrease of nickel content might be related to the increase ofdeposition rate depending on the concentration. The X-ray diffraction analysis revealed peakintensification in the {111} orientation of plane in the presence of a concentration of 10-6 M; this maybe in agreement with the results of metallographic study which showed that the coatings are adherentand have a good resistance. Hence, the Vickers microhardness of deposited coatings has a better value(376 HV) at the concentration 10-6 M. The corrosion resistance in 3% NaCl solution has been provenat the same concentration as found. Finally, the cyclic voltammetry and electrochemical impedancespectroscopic studies revealed that the additive strongly influences the cathodic process and affectsslightly oxidation of hypophosphite.