The hydrothermal synthesis, solubility and crystal growth of YVO4 and Nd:YVO4

In this paper we report the synthesis, solubility and growth of large YVO4 and Nd:YVO4 transparent single crystals in aqueous NaOH under hydrothermal conditions. YVO4 crystals formed from hydrothermal spontaneous nucleation by (1) reaction of Y2O3 and V2O5, (2) reaction of Y2O3 and Na3VO4 or (3) recrystallization of Czochralski-grown YVO4. Crystals synthesized by these hydrothermal methods were of good quality, exhibiting no signs of vanadium reduction. YVO4 was found to have a positive solubility coefficient from 375 to 500 °C in 2–6 M NaOH, as well as a positive dependence on mineralizer concentration. Single crystals of YVO4 and Nd:YVO4 were grown on YVO4 seeds using 2 M NaOH as a mineralizer and exhibited the expected tetragonal morphology. Growth rates between 0.097 and 0.13 mm/day were observed. Nd:YVO4 growth using temperatures of 450 °C in the dissolution zone and 410 °C in the growth zone produced a crystal 15×15×7 mm3 in size after a 4-week growth period.