Study of the Surfactant Role as a Particle Size Controller of Strontium Hexaferrite Magnetic Powder Synthesized by Surfactant-Assisted Sol-Gel Auto-Combustion Method


In this research using starting materials of ferric nitrate, strontium nitrate, citric acid and trimethylamine and by the sol-gel auto-combustion method, was produced strontium hexaferrite powder. The effect of adding the hydrocarbon of tetrabutylammonium bromide and surfactant of
n-decyltrimethyl ammonium bromide on the formation temperature and particles size of resultant powder was investigated. FTIR results showed the Occurrence of more complete combustion reaction in the samples with hydrocarbon and surfactant. According to the XRD results, single-phase strontium hexaferrite is formed in sample without additive by calcination at 900 °C, while in samples with hydrocarbon and surfactant formed at 850 and 800 °C, respectively. With addition of surfactant, grains and particles size decreased significantly.