Low temperature preparation and characterization of TiO2 nanoparticles coated glass beads by heterogeneous nucleation method

Nano-TiO2/glass beads composite particles were prepared using heterogeneous nucleation method at low temperature (80 °C). The microstructure and micro-morphology of the as-prepared samples were characterized by SEM, XRD, Raman, XPS and BET. Different concentrations of phytic acid solution were used to modify the surfaces of glass beads before the precipitate of TiO2 nanoparticles films. The results show that phytic acid plays an important role in the growth and micro-morphology of TiO2 nanoparticles on the surfaces of glass beads. It was found that the specific surface areas of the composite particles were 4, 45 and 38 times that of the pristine glass beads when the concentration of phytic acid was 0, 3.0 and 6.0 g/L, respectively. XPS analysis shows that a TiO2 layer is formed on the surfaces of glass beads through TiOSi bonds. XRD and Raman spectra of the TiO2 samples prepared by blank experiments without glass beads indicate that the crystal type of TiO2 is anatase. The wear-resistance of silicone-modified epoxy resin was largely improved when nano-TiO2/glass beads composite particles were filled in the matrix, especially for the samples pretreated with 3.0 g/L phytic acid. The main reason concerns the fact that TiO2 nanoparticles evenly loaded on the surface of glass beads were necked together, forming a rough and porous-structured coating layer when pretreated with 3.0 g/L phytic acid.