Photoelectric and optoelectronic effects of hard ferromagnetic manganese cobalt (Mn–Co) ferrite nanoparticles for high-frequency device application.

The effect of doping Mn2+ ions with cobalt ferrite (CoFe3O4) is examined. The photoelectric and optoelectronic behaviors of manganese cobalt ferrite (MnxCo1-xFe3O4) nanomagnetic samples grown by co-precipitation were examined. The effect of cation redistribution on octahedral sublattice site-B and tetrahedral sublattice site-A was investigated. X-ray analysis revealed the formation of Fe-phase in trivalent state and single-phased cubic spinel framework that exhibit a preferred orientation along (311) reflection plane. The crystallite size was determined by Scherer equation with values ranging between 9.02 nm and 32.64 nm. The Mn2+-rich Mn–CoFe2O4 nanoparticles exhibit low optical losses, whereas Mn2+-poor Mn–CoFe2O4 samples exhibit high optical losses. FTIR analysis revealed the presence of metal oxide, hydroxyl group and carboxylic group in the ferrite samples. The EDX plot provides evidence of the presence of Mn2+, Co2+, Fe3+, and O2− ions in proper ratio confirming the desired stoichiometric composition. Mn2+-rich Mn–CoFe2O4 samples showed the formation of enhanced photoelectric conductivity and photodiode characteristics. Optical analysis showed that Mn2+-rich Mn–CoFe2O4 nanoparticles are suitable as infrared (IR) detectors, optoelectronic devices and ultraviolet detectors. VSM measurements showed an increase in magnetic saturation and decrease in coercivity as Mn2+ ion composition is increased. Photoluminescence (PL) spectroscopy revealed the emission of a series of colors, such as violet, green and yellow at different wavelengths. Mn–Co ferrite exhibits multi-magnetic domain structure and is hard magnetic material due to Hc > Mr/2, and it is useful for high-frequency device applications. [ABSTRACT FROM AUTHOR]