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Hollow graphitic carbon nanoparticles (HGCNs) obtained by catalytic graphitization of acetylene carbon black (ACB) were investigated using ultra-soft X-ray emission spectroscopy. The electronic structures of the ACB HGCNs were compared with those of HGCNs obtained from iron carbide-filled carbon nanocapsules (Fe 3 C@CNCs) and Q-graphenes. The occupation of the p subband decreased in the following sequence: Fe 3 C@CNC HGCNs > ACB HGCNs > Q-graphenes. This sequence can be explained by changes in the occupations of the C2p states due to the formation of bonds between carbon and residual metal atoms within the HGCNs. It was also found that the contribution of the overlapping of pppCpps-states in the ACB HGCN walls toward the spectra of the HGNCs was greater in comparison with the reference Q-graphenes. It was established that ACB was not fully transformed into the HGCNs. Scanning and transmission electron microscopy methods were used to study the spatial structures and morphologies of the fabricated HGCNs.

Investigations of the electronic structure of graphene nanosheets synthesized by the reduction of oxidized graphene nanosheets were carried out using ultra-soft X-ray emission spectroscopy (USXES). Oxidized graphene nanosheets were produced from carbon nanofiber starting material using a modified Hummers method. X-ray diffraction, and scanning and transmission electron microscopy investigations were used in addition to USXES to study the electronic structure evolution from carbon nanofibers to graphene nanosheets. The effect of the degree of corrugation of the graphene nanosheets on the fine structure of the CK(alpha)-emission bands was revealed by USXES. It was found that corrugation of the graphene nanosheets is caused by overlapping of the pi-orbitals and formation of mixed (sigma + pi)-states.

Iron-doped indium-tin oxide (ITO) thin films with reduced to 50% mass indium oxide content are deposited onto glass substrates preheated at 523 K by co-sputtering of ITO and Fe 2 O 3 targets in mixed argon-oxygen atmosphere. The influence of different radio frequency (RF) plasma power for deposition of Fe 2 O 3 target on the electrical, optical, structural, and morphological properties of the films is investigated by means of four point probe, Ultraviolet-Visible-Infrared (UV-Vis-IR) spectroscopy, X-ray diffraction and atomic force microscopy methods. The volume resistivity of 930 µΩ⋅cm and transmittance over 85% are obtained for thin films sputtered under optimum conditions. Iron doping results in significant improvement in films transmittance and increasing the crystallization temperature of ITO thin films.