Structural, magnetic, magnetostrictive and optical properties of Mn and Cu codoped cobalt ferrite

Magnetostrictive materials have been a sought-after multifunctional material due to their propensity to be used in applications such as sensors, actuators, transducers, and other magnetoelectric devices. Cobalt ferrite (CoFe2O4) is one such commonly used magnetostrictive material due to its high magnetostriction and low cost. This work deals with the synthesis of CoFe2O4 (CFO) by substitution of Cu2+ at the tetrahedral site, Mn3+ at the octahedral site, and simultaneous substitution of Cu2+ and Mn3+ at both sites followed by its subsequent characterization. Hydrothermal method was adopted to synthesize the aforementioned samples. The effect of doping was then studied by analyzing their structural, magnetic, morphology, magnetostrictive, and Mössbauer properties. The obtained results reveal that doping of the transition metal ions is crucial in determining the magnetostrictive characteristics of CoFe2O4. Sequential addition of Cu2+, Mn3+ and their simultaneous addition leads to an enhancement in the piezomagnetic coefficient (dλ/dH)max of the CFO system and considerably reduces the magnetic field corresponding to the peak piezomagnetic coefficient.