Hydrothermal method is a candidate in synthesising nano-materials under high pressure and at a temperature far above its boiling point of solvent employed at 1bar pressure in a tightly closed system. The term hydrothermal is when water is used as a solvent in the system. Solvothermal is a general term when other organic solvents are used [8,9]. The hydrothermal reaction has a lot of advantages and can be used to give high product purity and homogeneity, crystal symmetry, meta-stable compounds with unique properties, narrow particle size distributions and lower sintering temperature. It offers a wide range of chemical compositions, a single-step process, dense sintered powder, sub- micron to nano-particles with narrow size distribution using simple equipment, lower energy requirement, fast reaction time, lowest residence time, as well as for the growth of crystals with polymorphic modification and the growth of crystals with low to ultra-low solubility for other applications [8–11].