CoFe 2− x Cr x O 4 ferrites: synthesis, characterization and their catalytic activity

Chromium substituted cobalt ferrites CoFe 2− x Cr x O 4 ( x = 0; 1; 1.5) were synthesized through a soft chemistry method—the gluconate precursor route. The gluconate precursors were characterized by infrared spectroscopy (IR), ultraviolet–visible spectroscopy and thermal analysis. The spinel oxide powders were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), Mössbauer spectroscopy and Brunauer–Emmett–Teller N 2 adsorption–desorption analyses. XRD indicated the formation of the spinel-type phase with good crystallinity. The mean crystalline domains size decreased from 23.8 to 17.8 nm with the increase in the chromium content. SEM revealed faceted particles for which the particle sizes varied significantly with the chromium content. The chromium substituted cobalt ferrites were found to have high catalytic performance.