The new original method for the synthesis of bimetal-carbon nanocomposites of copper and cobalt (CuCo@C) of various compositions using synthetic humic acid as a carbon source has been developed. The technique includes the synthesis of humates of copper and cobalt, preparation of their mixture and its pyrolysis in a hydrogen atmosphere. For characterize the final product, the methods of diffraction, cyclic voltammetry, and scanning electron microscopy were used. Comparison of diffractograms of bimetal nanocomposites shown two systems of reflexes from fcc structures, which correspond to metallic copper and cobalt. Diffractometric measurements also indicate the amorphous nature of the carbon matrix. Carrying out the pyrolysis of the metal humates in the reducing atmosphere afford remove almost completely the contained oxygen from the final product, partly in the form of CO2, partly in the form of water. Ions of the transition metal in these conditions are reduced to the metal atoms, forming nanoparticles surrounded by carbon. The formation of a carbon matrix metal around nanoparticles, on the one hand, can ensure their high thermal stability, and on the other hand, contributes to the stabilization of metal nanoparticles and prevents their aggregation. The size of cobalt nanoparticles in nanocomposites varies from 35 to 54 nm, and copper nanoparticles - from 56 to 88 nm, depending on the ratio used in the synthesis of metal humates. It was found that nanoparticles of an alloy of these metals (alpha-cobalt phase) are formed in nanocomposites containing 20% copper and 80% cobalt. Cyclic voltammogrames of bimetallic nanocomposites indicate the presence of dead pores in their composition. It has been established by scanning electron microscopy that in the case of an excess amount of copper in the nanocomposites, spherical formations about 1000 nm in size with faceting signs are formed. As part of the «bottom up» concept proposed a three-stage model of formation.
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