ИСТИНА

Carbon nanostructures such as carbon nanotubes, graphene, nanofibers, flakes, soot, onion-like structures have been extensively used in microelectronics, energy storage devices, sensors, catalysis, sorbents etc. Present talk describes their main features and stress the molecular nature allowed the surface modification by reaction, typical for organic substances. Depending on the texture CNMs can be divided into one-, two-, and three-dimensional structures. In the frameworks of their characterization it is worth to mention that even for the almost ideal structure of highly oriented pyrolytic graphite (HOPG) X-Rays photoelectron spectroscopy (XPS) show the difference between composition of the surface and bulk material. It is expressed in oxygen-containing surface groups, playing the key role for understanding the properties of carbon nanostructures. They provide intermediate or quasi-molecular position between solid state matter and molecule. They can simultaneously combine the properties of nanoparticles as a material and chemical properties as a substance. As nanoparticles they can be characterized by structure, size and shape and these properties are expressed in porous characteristics, electronic properties and phase composition. Chemical properties are manifested at the molecular level and expressed in surface modification, doping, and thermal degradation that mostly determined by surface groups. According to various estimations the global emission of carbon aerosols into the atmosphere is near to 240*106 t/year. Its main sources are emissions of combustion products of biomass during forest fires fossil fuels. Carbon can be found in atmosphere in elementary form and in the composition of various organic compounds. Another important source of carbon aerosols with a particle size less that 0.1 mkm are volcanoes. It explain the temperature anomalies after eruptions since absorb not only long-wave, but also short-wave radiation as well as ozone depletion, since it's O3 depletion coefficient γ = 3.3⋅10-3 that is for one order of magnitude higher that for Al2O3. Being hydrofobic and easily oxidizable, in the troposphere they rise sulfuric acid aerosol formation and wash out by precipitations. In the stratosphere, being covered by functional fragments, they exist much longer time. The present study was funded by Russian Foundation for Basic Research, project 19-05-50076 "Micromir".