Enhanced infrared radiation properties of CoFe2O4 by doping with Y3+ via sol-gel auto-combustion

CoFe2−xYxO4 (x=0, 0.05, 0.10, 0.15, 0.20, 0.25) ferrites were synthesized using a sol-gel auto-combustion method. The auto-combustion behavior of the dried gels and the effects of the Y3+ content and the sintering temperature on the infrared radiation properties of CoFe2−xYxO4 ferrites were investigated by FTIR, TG/DSC, SEM and XRD techniques. The results showed that the CoFe2−xYxO4 dried gels exhibited an auto-combustion behavior at room temperature once they were ignited in air. The Y3+ content and the sintering temperature were the two important parameters for enhancing the infrared radiation properties of CoFe2−xYxO4 ferrites, reflected by the crystalline phase and the lattice strain. The highest infrared emissivity of 0.95±0.01 was obtained from CoFe1.80Y0.20O4 after sintering at 600 °C for 2 h, which was 4.40% higher than that of CoFe2O4.