**1.8. Ultrasonic cavitation method**

Ultrasonic cavitation chemistry is useful for synthesizing a variety of compounds at milder conditions. The major advantage of this method is that it affords a reliable and facile route for the control of both the synthetic process and nanostructure of advanced materials. This process also provides chemical homogeneity and reactivity through atomic level mixing and phase pure crystalline materials can be prepared by annealing at reduced temperatures. In addition, the use of additive components (stabilizers or surfactants, precipitants) and particular calcination requirements are avoided [16].
