Abstract
The structural and optical properties of Zn-ion doped CoCr2O4 multiferroic materials were investigated in this work. We successfully synthesized Co1−xZnxCr2O4 (x=0, 0.2 and 0.4) polycrystalline samples using the conventional solid-state reaction route method. The XRD pattern confirmed the cubic spinel structure of the Zn-doped CoCr2O4 samples, with the Fd3m space group. The Williamson–Hall (W–H) and Debye–Scherrer techniques were employed to determine the crystalline size of the cobalt chromite system. The average crystalline sizes, calculated using the Debye–Scherrer formula, were found to be 35nm, 34nm and 32nm, for the CoCr2O4, Co0.8Zn0.2Cr2O4, and Co0.6Zn0.4Cr2O4 samples, respectively. These results show that the crystalline size calculated using the Debye–Scherrer formula decreased with an increase in Zn doping. We observed from the Raman spectra, the presence of three distinct bands at 188cm−1 (F2g), 504cm−1 (F2g), 662cm−1 (A1g) and one weak band at 434cm−1(Eg). These Raman bands are also present in the Zn-doped CoCr2O4 system, indicating structural stability even with doping. The energy band gap, calculated using the tauc plot, was determined as 3.15eV, 3.24eV and 3.27eV for CoCr2O4, Co0.8Zn0.2Cr2O4 and Co0.6Zn0.4Cr2O4 samples, respectively. The formation of the cobalt chromite spinel system was further confirmed by the FT-IR spectra.
