Zirconia microparticles produced by sol-gel synthesis have great potential for photonic applications. To this end, identifying synthetic methods that yield reproducible control over size uniformity is mportant. Phase transformations during thermal cycling can disintegrate the particles. Therefore, understanding the parameters driving these transformations is essential for enabling high-temperature applications. Particle morphology is expected to influence particle processability and stability. Yttria-doping should improve the thermal stability of the particles, as it does in bulk zirconia.