Quasicubic α-Fe₂O₃ nanoparticles embedded in TiO₂ thin films grown by atomic layer deposition

Monodispersed quasicubic α-Fe₂O₃ nanoparticles were synthesized from ferric nitrite (Fe(NO₃)₃), N,N-dimethyl formamide and poly(N-vinyl-2-pyrrolidone). Layers of nanoparticles were attached to HF-etched Si substrates by dip coating and subsequently embedded in thin titanium oxide films grown by atomic layer deposition from TiCl₄ and H₂O. The deposition of TiO₂ onto Fe₂O₃ nanoparticles covered the nanoparticles uniformly and anatase phase of TiO₂ was observed in Si/Fe₂O₃/TiO₂ nanostructures. In Si/Fe₂O₃/TiO₂ nanostructure magnetic domains, observable by magnetic force microscopy, were formed and these nanostructures implied ferromagnetic-like behavior at room temperature with the saturative magnetization and coercivity of 10 kA/m. - Highlights: • Cubic-shaped iron oxide crystallites were supported by thin titanium oxide films. • The process chemistry applied allowed formation of heterogeneous composite. • Atomic layer deposition of titanium oxide on nanocubes was uniform and conformal. • The nanostructures formed can be regarded as magnetically susceptible materials.