Aqueous sol-gel synthesis of zirconium titanate (ZrTiO ₄) nanoparticles using chloride precursors

Zirconium titanate powders were synthesized by a straightforward sol-gel method using zirconium and titanium chlorides as metal precursors, deionized water as solvent and oxygen donor, and a NaOH solution for adjusting pH to 7. According to transmission electron microscopy, amorphous particles of nearly 5 nm in size with a relatively spherical morphology were prepared. Thermogravimetry and differential scanning calorimetery analyses on the xerogel at a heating rate of 10 °C/min indicated a crystallization temperature of 690 °C, which is comparable with previous reports. Furthermore, via differential scanning calorimetery studies using the Kissingers equation, the activation energy for ZrTiO ₄ crystallization was determined to be 850 kJ/mol. Structural evaluations in the isothermal regime, using X-ray diffraction experiments, implied the onset of ZrTiO ₄ crystallization at 550 °C.