Gold nanocluster properties exhibit unique size-dependence. In this contribution, we employ reactive molecular dynamics simulations to calculate the size- and temperature-dependent surface energies, strain energies and atomic displacements for icosahedral, cuboctahedral, truncated octahedral and decahedral Au-nanoclusters. The calculations demonstrate that the surface energy decreases with increasing cluster size at 0 K but increases with size at higher temperatures. The calculated melting curves as a function of cluster size demonstrate the Gibbs-Thomson effect. Atomic displacements and strain are found to strongly depend on the cluster size and both are found to increase with increasing cluster size. These results are of importance for understanding the size- and temperature-dependent surface processes on gold nanoclusters.

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Synthesis of size-controlled anisotropic magnetite (Fe3O4) nanoparticles allows designing next-generation magnetic nanosystems with predetermined magnetic properties suited for particular applications in biomedical, information, and environment. In this work, we report...

Thermoactivated structure rearrangements of a binary CuAu alloy at the micro-, meso-, and macrolevels are investigated under deviation from stoichiometry. Mechanisms of these rearrangements at the micro-, meso-, and macrolevels are identified.

In this work, we studied possibility to obtain bimetallic nanopowders by our modified solution combustion synthesis method using citric acid as a fuel. Stoichiometric amounts of metal nitrates with metal to metal ratios 1:1 and 1:2 and fuels with final oxidizer to fuel ratio of 1.75 were used as initial components to prepare aqueous solutions. The almost complete absence of metal oxide phases was confirmed by energy-dispersive X-ray spectroscopy. The X-ray diffraction analysis of obtained materials showed that all samples are pure bimetallic nanopowders with distorted cubic crystal structure of each metal. According to high resolution transmission electron microscopy the mean diameter of metallic particles are about 10 nm for all nanopowders. The calculated interplanar distances of crystals of metal particles as well as detailed scanning transmission electron microscopy studying showed uniform distribution of different metal spices into nanoparticles. Thus, we can conclude the nanopowders are bimetallic particles with co-integrated crystal structures of different metalic spices. We suppose, the possibility of solution combustion synthesis of bimetallic nanopowder in the air environment is due to a combination of type and amount of the fuels as well as technological conditions of the synthesis. These lead to rapid combustion process at low temperature. In addition, protective inert atmosphere appears above freshly synthesized metal nanopowders during thermal decompositions of the fuels that eventually prevent metal oxidation. Modified SCS method could be successfully used for one-step synthesis of complex oxide-oxide and metal-oxide core-shell nanostructures. For citation: Romanovskii V.I., Khort A.A., Podbolotov K.B., Sdobnyakov N.Y., Myasnichenko V.S., Sokolov D.N. One-step synthesis of polymetallic nanoparticles in air invironment. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 9-10. P. 42-47