We have reviewed a possibility of hardening and modifying nanocomposite materials' properties by creating spatial nanolayers of a space charge on the surface of nanocrystals by using nanostructures from allotropic forms of carbon with a high electron affinity. They can be used as free electrons' traps that generate a negatively charged nanolayer of the space charge on the surface of the hardened material. This changes the physical properties of the nanostructured composite (its strength and luminescence properties). In this paper, composite coatings made of both copper and carbon have been experimentally studied. The Cu-C composite coatings' samples were produced by high-speed ion-plasma magnetron sputtering with mosaic target. These coatings do not interact with each other metallurgically. Nanostructure, roughness, mechanical properties, and electric properties of coatings depend on the Cu:C ratio. So, 10 atomic%-15 atomic% Cu concentration results in to reduction of the dry friction coefficient up to 0.1 and increase of the wear resistance up to 10-17 m3 N m. The mechanical properties can be explained by the free electrons capture with the carbon nanostructures and space charge formation. © 1973-2012 IEEE.