Preparation and characterization of novel magnetic ZrO2/TiO2/Fe3O4 solid superacid

Novel magnetic solid superacids were prepared by introducing TiO2 and magnetic substrates by chemical co-precipitation method. The prepared materials were characterized by means of XRD, FT-IR, DSC and TEM techniques. The results indicated that the introduction of TiO2 and magnetic substrates markedly hindered the phase transformation from tetragonal phase (t-ZrO2) to monoclinic phase (m-ZrO2) even calcined at 1200 °C. Furthermore, the solid superacids doped with magnetic substrates presented the superparamagnetic property. The morphology of the samples showed lamellar crystals with high purity and uniform size distribution, and the (101) lattice plane (d = 0.29 nm) could be clearly seen in the HRTEM image.