Synthesis and characterization of NaAlSi2O6 jadeite doped with different metallic oxides under high pressure and high temperature

Abstract

According to the mineral composition [Formula: see text] of jadeite, [Formula: see text] and [Formula: see text] with a molar ratio of 1:1 were selected as raw materials. One sample was undoped, and five samples were mixed with 0.4 wt.% [Formula: see text], MnO, CoO, [Formula: see text] and [Formula: see text], respectively. The experimental studies were executed under the synthetic condition of 5 GPa pressure and [Formula: see text] temperature using China-type large volume cubic high-pressure apparatus (CHPA) (SPD-6X1200). After the experiment, compositions of the synthetic jadeites were characterized by X-ray diffraction, microstructures characterized by field emission scanning electron microscopy (FESEM) and the high-resolution transmission electron microscopy (HRTEM), molecular vibration types investigated by Raman spectra. The color-causing ion of the synthetic jadeites was investigated by UV–Vis Spectra. The results show that the synthetic jadeites have excellent crystallinity and fine-grained texture and similar structural behavior with natural jadeite. UV–Vis Spectra indicated that different colors of samples have different ion absorption peaks, thus showing different colors. This experiment explored the geological conditions of synthetic jadeite by means of high pressure and high temperature (HPHT) to give a favorable experimental basis for synthetic jadeite and analyze the coloration mechanism of jadeite by way of ion-doping.