Structural, optical, elastic and magnetic properties of Ce and Dy doped cobalt ferrites (original) (raw)

The CoCe x Dy x Fe 2-2x O 4 (x ¼ 0.0, 0.01, 0.02, 0.03, 0.04, 0.05) have been prepared by sol-gel auto-combustion technique. The structural result confirmed the formation of single phase cubic spinel structure showed by XRD. Crystallite size obtained from the XRD is in the range of 24e28 nm, whereas particle size obtained from the transmission electron microscopy is in the range of 20e30 nm. It is also found that the cation distribution of CoCe x Dy x Fe 2-2x O 4 resulted in the Fe 3þ and Co ions occupy both tetrahedral A-site and octahedral B-site, whereas Ce and Dy cation distributed in both of them. The photoluminescence (PL) analysis reveals that all prepared samples contain four bands; (i) peak centered at 412 nm corresponding to ultraviolet (UV) band i.e. near band edge emission, (ii) a high intensity peak centered at 434 nm belonging to violet band, (iii) a low intensity and sharpness peak positioned at 466 nm refers to blue band, and (iv) a broad and very low intensity peak observed at 502 nm assigned to green band. FTIR results of the prepared samples showed that two vibration bands between 600 cm À1 and 400 cm À1 belonging to the stretching vibration of tetrahedral metal-oxygen bond (v A) and stretching vibration of octahedral site (v B) respectively. M€ ossbauer spectroscopy has also been performed to investigate the hyperfine structure of undoped, Ce and Dy co-doped cobalt nano ferrites. The higher values of M S and H hf for x ¼ 0.01 composition can be attributed to the occupation of Dy 3þ ions in octahedral site whereas the Ce 3þ ions occupied to tetrahedral site.