One-step combustion synthesis of SiO2–CoFe2O4 nanocomposites and characterization for structural, thermal, optical and magnetic properties

Abstract

In this study (1-x)SiO2-xCoFe2O4 (x = 0,0.2,0.4,0.8,1) nanocomposites were synthesized using the sol-gel auto-combustion route and structure, morphology, thermal, optical and magnetic properties of as-prepared samples were investigated. X-ray diffraction followed by Williamson-Hall analysis revealed the formation of pure cobalt ferrite (CFO) nanoparticles and SiO2-CFO nanocomposites. Scanning electron microscope (SEM) images showed that SiO2 matrix serves as a physical barrier to control the morphology and size of cobalt ferrite nanoparticles and prevents nanoparticles agglomeration. Diffuse reflectance UV–Vis spectroscopy analysis showed that the optical band-gap of SiO2-CFO nanocomposites decreases from 1.23 eV to 1.12 eV with increasing the concentration of cobalt. Finally, the vibrating sample magnetometer (VSM) analysis that as cobalt ferrite content increases, the magnetic properties of nanocomposites improved. These nanocomposites could be applicable as a magnetic photo-catalysts.