Influence of the fuel composition and the fuel/oxidizer ratio on the combustion solution synthesis of MgFe2O4 catalyst nanoparticles

Solution combustion synthesis (SCS) has been widely applied to produce oxide catalysts due to the possibility of producing highly pure and hom- ogeneous nanostructured powders at low cost. The smaller the particles are and the higher the surface area is, the more efficient the powder catalyst will be. For iron-based catalysts such as ferrites, the degree of spinel inversion is another factor that affects the catalyst activity. In SCS, the particle size, surface area, and degree of spinel inversion are fundamentally related to process variables such as the fuel composition and the fuel/oxidizer ratio. Therefore, we studied the application of glycine and polyethylene glycol - 200 molecular weight (PEG 200) as fuels and the influence of the fuel/oxidizer ratio in the SCS of MgFe2O4 catalyst nanoparticles. The products' morphology and composition were systema- tically characterized by X-ray diffraction, microscopy analyses, and specific surface area. The results indicate the production of high-purity nanoparticles with increased surface area, which was obtained with low concentrations of glycine and a wide range of particle sizes that depend on the fuel composition and concentration.