Effects of surfactants on the structure and crystal growth behavior of Sm2Zr2O7 nanocrystalline

Sm2Zr2O7 nanocrystallines were synthesized via hydrothermal method using polyethyleneglycol (PEG), cetyltrimethyl ammonium bromide (CTAB) and sodium dodecylbenzene sulfonate (SDBS) as surfactants, respectively. The effects of surfactants on the structural evolution and the crystal growth of Sm2Zr2O7 were investigated by X-ray diffraction (XRD), thermogravimetric analysis and differential scanning calorimeter (TG/DSC), Raman spectroscopy, field emission scanning electron microscope (FESEM) and high resolution transmission electron microscopy (HRTEM), separately. The as-prepared products have a spherical morphology, and the average particle sizes are in the range of 4–9 nm. The structure transition from fluorite to pyrochlore structure occurred at 1300 °C with PEG and SDBS, which can be restrained by adding CTAB. The activation energy of crystal growth is significantly dependent on the surfactants, which is in the order of SDBS > PEG > CTAB. Moreover, the effects of surfactant on the sintering-resistance property of the products are also discussed.

The surfactants have a significant effect on the activation energy of crystal growth which is with the order of SDBS > PEG > CTAB.Figure optionsDownload as PowerPoint slideHighlights
► CTAB can restrain the phase transition from fluorite to pyrochlore structure.
► CTAB has a significant effect on the particle size and the dispersion of products.
► The activation energies of crystal growth are in the order of SDBS > PEG > CTAB.
► CTAB has a significant role on the sintering–resistance property of the products.