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We propose a simple and dry technique to functionalize and dope single-walled carbon nanotubes (SWCNTs) with ozone. The doping under ozone-controlled conditions (300 mg/h) during 30 min was shown to give a 4-fold decrease in the sheet resistance of SWCNT films (148 Ω/square at the transmittance of 90%). Further ozone treatment of the SWCNTs leads to deterioration in the film conductance. The conductivity alteration is discussed in the light of the Criegee mechanism, oxidation and charge transfer during the ozone exposure. The samples were characterized by TEM, FT-IR, Raman, UV–vis–NIR, and XPS to confirm the findings of the work. The ozone-treated samples show increased hydrophilicity with increasing ozone treatment time, which makes possible to coat the SWCNT samples with inorganic materials. SWCNTs after ozone treatment can be successfully and uniformly coated by ZnO with the help of atomic layer deposition (ALD) technique.

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The FeCoNiCrMo0.5Alx system with x up to 2.13 was analyzed from the point of view of evolution of the phase composition and microstructure. Cast samples were synthesized by induction melting and analyzed by X-ray diffraction, energy dispersive spectroscopy, scanning electron microscopy, and Vickers microhardness test methods. Phase compositions of these alloys in dependance on Al concentration consist of FCC solid solution, σ-phase, NiAl-based B2 phase, and BCC solid solution enriched with Mo and Cr. Phase formation principles were studied. Al dissolves in a FeCoNiCrMo0.5 FCC solid solution up to 8 at.%.; at higher concentrations, Al attracts Ni, removing it from FCC solid solution and forming the B2 phase. Despite Al not participating in σ-phase formation, an increase in Al concentration to about 20 at.% leads to a growth in the σ-phase fraction. The increase in the σ-phase was caused by an increase in the amount of B2 because the solubility of σ-forming Mo and Cr in B2 was less than that in the FCC solution. A further increase in Al concentration led to an excess of Mo and Cr in the solution, which formed a disordered BCC solid solution. The hardness of the alloys attained the maximum of 630 HV at 22 and 32 at.% Al.