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latter requires less computer resources but also allows monitoring how the crystal
environment reacts to the structural changes in the active centers of the surface.

This approach then lays a foundation for building theoretical models corresponding
to the current level of detailing corrosive-electrochemical processes.

Moreover, we have established the physical and chemical laws of structural
and energetic degradation of binary platinum nanoclusters with the shell structure

of Pt 42Me 13 (Me – Cr, Fe, Co, Ni, Ru) and different composition under the

influence of corrosive components, and shown that transition metals, which make

up the core of such nanoclusters, significantly affect their adsorption characteristics

and corrosion-morphological durability of a surface in the low-temperature fuel

cell environment. In particular, we have shown that in the environment containing
–
+
–
H 2O, Cl , OH , H 3O the hydrophilicity of the model nanoclusters increases in the
row of Pt 55< Pt 42Cr 13< Pt 42Fe 13< Pt 42Co 13< Pt 42Ni 13, which, in turn, facilitates the
n+
–
n-1
–
n+
n-1
formation of [Pt (OH )(H 2O) 3] and [(Pt Cl )H 2O] complexes. These
complexes have a higher release barrier from the surface of Pt 42Ru 13 and Pt 42Co 13
nanoclusters as compared to Pt 55, which suggests their higher resistance towards
degradation in the afore-mentioned environment.

We have also unraveled that binary nanoclusters Pt 42Co 13 with the shell

structure have a lower reactivity towards oxidation and formation of a weaker

chemo-absorption bond between the surface platinum atoms and atomic oxygen in

comparison to the pure platinum nanoclusters. This phenomenon is based not only

on the change in the interatomic distances Pt–Pt, but also on the electron

characteristics of the cobalt atom from the undersurface layer, which is positioned

in a particular tree-coordinate space, which, in turn, explains the experimentally

determined more beneficial characteristics of platinum-cobalt nanoclusters.

We have also introduced a unit of an energetic activity to be used for the

practical evaluation of the corrosion-morphological stability of the binary platinum

nanoparticles with the shell structure in the environment. This unit’s determined by

the ratio of the calculated cohesive energies of binary and monoplatinum

nanoclusters during their interaction with the components of the environment.