An analysis of the experimental data related to the mechanism of Pt particles sintering has been carried out using the modified LSW theory. The size distribution for the Pt nanoparticles at the stage of Ostwald ripening fits the generalized Lifshitz-Slyozov-Wagner model calculated with the assumption of two parallel mechanisms involved in the nanoparticles growth (dissolution): diffusion and Wagner’s (controlled by the chemical reaction rate). Comparison between the experimental histograms and the curves calculated theoretically proves the governing role of the Wagner’s mechanism (chemical reaction) in the Pt nanoparticles growth.

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A generalized Lifshits−Slezov−Wagner distribution for nanoclusters or nanocrystals growth according to two parallel mechanisms (Wagner and diffusion) has been used to explain a series of experimental histograms, which cannot be correctly related to the Wagner or the Lifshits− Slezov distribution separately. A process of the nanoclusters growth at the Ostwald ripening stage of the phase transformation in the solid systems can be correctly described using the generalized distribution of Lifshits−Slezov−Wagner. The Ostwald ripening stage is also present in a process of formation of a new semiconducting nanoclusters phase (phase transformation of the first type) during chemical synthesis of nanoclusters in the liquid medium. That is why the Lifshits−Slezov− Wagner theory can be used for analysis of the mechanism and kinetics of the ZnO and SnS nanoclusters formation from supersaturated solutions. The theory should be modified taking into account possible joined influences of both (Wagner and diffusion) mechanisms on the process of the growth of the nanoclusters. As a result, the SnS nanoclusters experimental histograms were found in good correlation with the generalized distribution of Lifshits−Slezov−Wagner at various values of x. The rate of the nanocluster's growth is controlled mostly by formation of new chemical bonds or a surface chemical reaction, which runs on the nanocluster's surface. The growth of the ZnO nanoclusters can be controlled by any of the Wagner's or diffusion mechanisms. The growth rate constants were estimated by means of comparison between experimental and theoretically calculated temporal changes in the average radii or average diameters of nanoclusters. These constants can be used to optimize technological conditions for synthesis of nanoclusters from supersaturated solutions. A method of evaluation of an important energetic parameter, specific surface energy, on the nanocluster/solvent interface is also proposed in this article.

The review deals with analysis of the kinetics of Ostwald ripening of nanodispersed phases in metal alloys when the growth (dissolution) of the nanoparticles of the reinforcing phase is controlled simultaneously by the  matrix diffusion, diffusion through the dislocation tubes and the rate of the atoms transition through the interphase boundary (Wagner's mechanism of growth). As a rule, different mechanisms of the nanoparticles growth (dissolution) are simultaneously employed in the process of the particles ripening while the number of the mechanisms involved in the growth (one, two or three) depends on various factors such as: chemical composition of the nanodispersed phases, conditions of exploitation (changes in mechanical loads, temperature regimes, environmental conditions), technological conditions of synthesis, etc. The possibility of practical implementation of the proposed mechanisms of growth of nanoparticles in the Ostwald ripening process can be confirmed or declined by a comparison between the experimental and theoretical data. As seen from the comparison between some experimental histograms with the lines built theoretically, the proposed mechanisms of growth of the dispersed phase nanoparticles seem realistic.

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