Photocatalytic and bactericidal activities of hydrothermally and sonochemically prepared Fe2O3–SnO2 nanoparticles

Fe2O3–SnO2 nanocomposites (NCs) were prepared by hydrothermal and sonochemical methods. Transmission electron micrographs confirmed that the composites comprise nanoparticles. Energy-dispersive X-ray analyses revealed compositions of 25 at.% Sn and 22 at.% Fe for hydrothermally prepared NC (HNC) and 4 at.% Sn and 56 at.% Fe for sonochemically prepared NC (SNC). X-Ray diffractograms revealed rutile SnO2, γ-Fe2O3, and FeO(OH) as components of HNC, and rutile SnO2, γ-Fe2O3, β-Fe2O3 and FeO(OH) of SNC. Both NCs absorb visible light and display red emission. The solid-state impedance spectrum for HNC is a half-semicircular arc and SNC exhibits a quasi-linear relationship between Z′′ and Z′. Both NCs are ferromagnetic. The saturation magnetization of HNC is much less than that of the SNC, which in turn is far less than that of the γ-Fe2O3 precursor. Both NCs display visible light photocatalysis and HNC is a better photocatalyst than SNC. Furthermore, both NCs exhibit bactericidal activity.