Pulsed plasma chemical synthesis of Fe₂O₃@TiO₂ core–shell nanocomposites

The Letter presents the results of the experimental investigation on the synthesis of core–shell structured nanocomposites. Iron oxide, which served as a nucleus in the composite, was synthesised using the plasma dynamic method. The composite shell was titanium oxide produced by the pulsed plasma chemical method. Average sizes of nanoparticles were estimated between 50 and 150 nm in the Fe₂O₃@TiO₂ core–shell structured composite nanoparticles using TEM. A distinctive feature of the morphology of the synthesised Fe₂O₃@TiO₂ core–shell is that the core entirely encapsulates clusters of titanium oxide nanoparticles. The wall thickness of the coating is 5–10 nm. The spectral dependence of the absorption coefficient α(hν) was calculated for the Fe₂O₃@TiO₂ composite. The interband absorption parameters are determined in the energy intervals Δ′(hν) upon approximation of the absorption spectra. The bandgap for indirect and direct allowed transitions is 1.36 and 1.97 eV for E^′′_g and E^′_g, respectively.