Preparation of Spherical Submicronic Barium Zirconate particles in Highly Basic Solution below 100°C

In this study, a new method has been developed to produce pure crystalline BaZrO₃ powders from Ba+Zr solution or weakly soluble reactants by using precipitation route in highly basic aqueous solution. The influence of several synthesis parameters is studied. At high OH⁻concentration ([NaOH] = 20 mol/l), it is possible to obtain the well-crystallized stoichiometric perovskite phase at relatively low temperature (∼80°C), after a short reaction time (15 minutes) and without requiring any precaution to avoid the presence of CO₂. This synthesis method yields spherical particles, whose size can be controlled by changing the concentration of the Ba+Zr solution. No calcination treatment is necessary since the precipitate is crystalline. Suitable choice of the synthesis parameters ([NaOH] = 20 mol/l, [Ba+Zr] = 1 mol/l, reaction time = 15 minutes) yields a sub-micron precipitate.