**1.3. Microwave combustion method**

This method is actually one of the most diffused due to its numerous advantages: is a wet chemical technique, enables fast reaction rate, chemical homogeneity, and high reactivity due to the uniform heating produced by microwaves. Some drawbacks are represented by the difficulty to vary the spherical form of particles and to control the valence states of the elements [10].


*Tunnels DOI: http://dx.doi.org/10.5772/intechopen.109608*

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