Magnetic properties of mesoporous cobalt–silica–alumina ternary mixed oxides

Mesoporous cobalt–silica–alumina mixed oxides with variable cobalt content have been synthesized through slow evaporation method by using Pluronic F127 non-ionic surfactant as template. N2 sorption analysis of the template-free mixed oxide samples revealed that these mesoporous materials have high BET surface areas together with large mesopores. Powder XRD, TEM, EDS, FT IR and EPR spectroscopic analysis have been employed to understand the nature of the mesophases, bonding and composition of the materials. Low temperature magnetic measurements of these mixed oxide materials show the presence of ferromagnetic correlation at elevated temperature though at low temperature paramagnetic to ferrimagnetic transition is observed.

Graphical AbstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Mesoporous cobalt–silica–alumina ternary mixed oxides. ► High surface area and mesoporosity in magnetic materials. ► Ferromagnetic correlation at elevated temperature. ► Low temperature paramagnetic to ferrimagnetic transition.