Novel Fabrication Of Monodispersed Peanut-type Celestine Particles Using Sr-edta Chelating Precursors

摘要

Novel monodispersed peanut-type SrSO_4 (celestine) particles have been prepared using a facile precipitation reaction of Sr-EDTA chelating precursors at ambient temperature. The as-formed products were studied by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen absorption-desorption and differential scanning calorimetry-thermogravimetry (DSC-TG) measurement. The monodispersed SrSO_4 particles with an average length of 1.7 μm and an aspect ratio of 1.4 appear unusual peanut-type morphology. These SrSO_4 particles have a relatively large Brunauer-Emmett-Teller (BET) surface area of about 20.9 m~2 g~(-1) and contain mesopores with a mean pore size of about 34.3 nm. The SrSO_4 particles exhibit an excellent thermal stability from room temperature to 1400 ℃ with a structural transformation at 1158.3 ℃. The growth mechanism of the monodispersed peanut-type celestine particles was discussed to obtain a better understanding on their formation process.