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

• 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.

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.