Long-range order in the spatial distribution of electrodeposited copper and silver nuclei on glassy carbon

The features of spatial distributions of metal nuclei (Cu, Ag) electrodeposited on glassy carbon (GC) were studied under potentiostatic conditions. A new approach was suggested to estimate inter-nuclei distances, which allows, considering the size of nuclei, to the changes in average distances between the nearest neighbor nuclei during their formation to be analyzed. To evaluate effectively the degree of deviation of experimental spatial distributions from Poisson and simulated homogeneous distributions, the statistical quantitative criterion of Romanovskyʹs correspondence was applied. The analysis of radial distribution functions of inter-nuclei distances and spatial distributions of average distances between the nearest neighbors during their formation showed that metal nuclei (Cu, Ag) electrodeposited at low and average overpotentials are distributed statistically ordered on the surface of GC. The ordering is obvious to virtue of the fact that specific inter-nuclei distances for which the value of Romanovskyʹs correspondence criterion is larger or equal to 3 obey a geometrical progression with a ratio q≈1.41. It was determined that the formation of the long-range order in the spatial distribution of copper and silver nuclei occurs under different mechanisms. It was demonstrated that the effect of the nearest neighbors determines the character of the spatial distribution of nuclei.