Effect of calcination temperature on structural, antibacterial, radiation shielding and magnetic properties of cubic spinel cobalt nanoferrite.

For the first time, Cobalt ferrite (CoFO) nanoparticles (NPs) were synthesized by solution combustion method using B i g T h y m e leaf extract as a reducing agent followed by varying the calcination temperature as-formed — 800 °C. At all the calcination temperatures, Bragg reflections matches well with FCC cubic spinel structure. Crystallite size increases from 12–79 nm with increase in calcination temperature. The SAED pattern and d-spacing from Transmission electron microscopy matches well with the PXRD pattern and the calculated crystallite size matches well with the Scherrer's formula. The direct energy band gap was found to be 1.55 eV. The effect of calcination temperature on different magnetic properties such as retentivity, coercivity, saturation of magnetization, squareness ratio and Bohr magneton was discussed in detail. Large coercivity (2.26 kOe) is observed at low calcination temperature. Further, X-ray/gamma radiation absorption parameters such as mass attenuation coefficient, half value layer and Z e f f are established which is an essential in the field of radiation dosimetry. CoFO NPs exhibited sensitivity against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. The cytotoxic properties were examined on cervical cancer HeLa cells and compared with the cisplatin drug. CoFO NPs shows higher % cell viability and less % cell death. Thus, CoFO NPs can be used as a drug carrier in cancer therapy. [Display omitted] • CoFe 2 O 4 are synthesized using Big Thyme leaves extract and characterized. • Magnetic, antibacterial and X-ray / gamma ray shielding properties are studied. • Facile, economical and efficient method is used for multiple applications. [ABSTRACT FROM AUTHOR]