A novel approach to synthesize mixed-metal oxides via direct metal combustion

A high-surface-area, magnetic iron‑aluminum spinel has been synthesized via direct combustion of iron and aluminum powders in a laminar dust burner. Characterization of the combustion products by SEM, EDAX, XRD, and BET revealed spherical nanoparticles comprised of hercynite (FeAl 2 O 4 ) and gamma-alumina ( γ -Al 2 O 3 ), formed due to high flame temperatures. The products exhibit a high specific surface areas (800 m 2 /g) and high porosity, indicating strong catalytic potential. • A laminar metal-air flame is used to synthesize spinel nanoparticles. • The obtained nanoparticles are porous and have a very high specific surface area. • The proposed method is a one-step, clean process.