Photoluminescent vitroceramic nanocrystals based on silica-stabilised zirconium, production method thereof and product based on the nanocrystals, for thermal barrier coatings

Photoluminescent glass ceramic nanocrystals based on silica-stabilized zirconia obtained through a process that contains the following steps:

• a preparing a precursor of SiO2 (tetraethoxysilane TEOS solution) by mixing tetraethyl orthosilicate with a primary alcohol in a ratio of tetraethyl orthosilicate:
• alcohol 0.1:15.5 with constant stirring for 1 hour and adding distilled water in a ratio of tetraethyl orthosilicate:
• water 0.1:2.8 for two hours and subsequently adding an inorganic acid selected from HNO3 or HCl and water in a mixing ratio of tetraethyl orthosilicate:
• acid:
• water of 0.1:0.0005:2.8 with constant stirring for 1 hour at room temperature and atmospheric pressure to obtain a TEOS solution;
• b) preparing a Zro2 solution by taking a zirconium (Zr+4) solution and adding ethyl alcohol and inorganic acid selected from HNO3 and HCl in a ratio of zirconium solution:
• ethyl alcohol:
• acid of 0.9:24.5:1.8 and stirring at room temperature and atmospheric pressure for a period of 1 hour;
• c) mixing the TEOS solution obtained in step a) and the ZrO2 solution obtained in step b) to form a SiO2—ZrO2 mixture, wherein the molar ratio of SiO2:ZrO2 is 10:90;
• d) adding to a mixture of Erbium in HNO3 solution in a ratio of 1% to the SiO2—ZrO2 mixture to obtain an Erbium mixture;
• e) agitating the Erbium mixture obtained in step d) for a period of 10 to 20 hours;
• f) depositing the Erbium mixture in a platinum crucible or a container made of platinum suitable for high-temperature thermal treatment;
• and
• g) thermally treating the mixture from step f) with a heating profile wherein the temperature is increased from room temperature to 900° C. at a rate of 18 to 20° C./minute;
• wherein said nanocrystals are characterized in that the X-ray diffraction pattern thereof presents with bands 2θ at 30.1, 34.6, 35.1, 42.9, 50.1, 50.5, 59.3, 60.0, 73.0, 74.3, 82.2 and 84.9 and where the nanocrystals have sizes between 7.5 and 12.5 nanometers.