scholarly journals Study of the influence of surface-active substances on the initial stage of copper electrodeposition

Author(s):  
Amantay Dalbanbay ◽  
Aleksandr Nefedov ◽  
Roza Nurmanova ◽  
Mikhail Nauryzbayev

In this research, the effect of surface-active substances (CMC and DFP) on the electrolysis of copper by cyclic voltammetry (CVA) and chronoamperometric methods was studied. The working electrode was a glassy carbon electrode. Studies show that in the acid solution of copper sulfate (10-2 M CuSO4 + 0.5 M H2SO4), the three-dimensional electrochemical deposition of copper occurs by the mechanism of instantaneous nucleation. The added surface active substances affect the dischargeionization process, the standard electroreduction potential is shifted to the negative side. The added DFP reduces the cathodic peak current, and the addition of CMC results in its increase. At the deposition potentials corresponding to the regions up to the CVA peak current (here, still, the mixed electrodeposition kinetics), the number of nuclei formed is greater for a pure solution, but at current decay potentials, where the diffusion regime takes place, the nuclei population density (NPD) is higher for solutions with surfactants. The most powerful effect here is caused by the addition of DFP. In the case of mixed additives, the NPD values are close to those of the CMC, obviously indicating the preferential adsorption of CMC, whereas the DFP as complexes with copper ions is closer to the near-electrode region.

2018 ◽  
Vol 913 ◽  
pp. 445-450 ◽  
Author(s):  
Jia Qi Ni ◽  
Ke Qing Han ◽  
Mu Huo Yu ◽  
Chen Yu Zhang

The initial stages of copper electrodeposition in acid copper sulphate/sodium citrate bath were investigated with varying copper and sodium citrate concentrations. Different electrochemical measurements, including linear sweep voltammetry, cyclic voltammetry, and chronoamperometry were introduced to the study. The Scharifker-Hills model was introduced to identify the nucleation model with analysing current transients. It was observed that the increase of copper ions inhibited the cathodic polarization behaviour for the reduction of ions. On the contrary, sodium citrate promoted the cathodic polarization behaviour. The chronoamperometry results indicated that without the sodium citrate, the nucleation process corresponded to instantaneous nucleation and three-dimensional diffusion limited growth, although obvious deviations were observed. While the addition of sodium citrate changed the deviations and caused that the initial deposition kinetics followed well with the mechanism of instantaneous nucleation.


1991 ◽  
Vol 111 (3) ◽  
pp. 1097-1104
Author(s):  
James Coticchia ◽  
Frederick Heiselman ◽  
Raouf Gharbo ◽  
Thomas Demaria ◽  
David Lim

2005 ◽  
Vol 20 (2) ◽  
pp. 253-258 ◽  
Author(s):  
Elisa Zeno ◽  
Bruno Carré ◽  
Evelyne Mauret

2021 ◽  
pp. 111215
Author(s):  
Irena Ciglenečki ◽  
Palma Orlović-Leko ◽  
Kristijan Vidović ◽  
Viša Tasić

Parasitology ◽  
1949 ◽  
Vol 39 (3-4) ◽  
pp. 281-290 ◽  
Author(s):  
A. R. Trim

1. The rate of penetration of some representative drugs into Ascaris lumbricoides var. suis has been measured.2. The series of 4-n-alkyl resorcinols shows a typical homologous series effect.3. l-Nicotine penetrates relatively slowly.4. Its rate of penetration is greatly influenced by the extent of dissociation of its methyl pyrrolidine basic group.5. The rate of penetration of nicotine is greatly accelerated in the presence of some surface active substances.6. Chloroform is the most rapidly penetrating substance studied, and its penetration is not significantly influenced by the presence of proteins, carbohydrates and fats and their products of digestion.7. An analysis of the experimental results shows that the outermost layer of the cuticle of Ascaris is probably the main barrier to penetration. It behaves as if it were a thin; homogeneous layer of lipoid.8. The significance of these results in the study of anthelmintics is assessed.


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