Single domain limit for NixCo1−xFe2O4 (0 ≤ x ≤ 1) nanoparticles synthesized by coprecipitation route

NixCo1−xFe2O4 (0 ≤ x ≤ 1) nanoparticles (sizes: 8–52 nm) were synthesized by chemical coprecipitation route. Single domain limit (dsdl) for the nanoparticles, determined from the coercivity (HC) versus particle-size curves, was explored as a function of nickel concentration (x). The coercivity of the particles attains a peak value at dsdl, and it was found that coercivity decreases linearly with increasing nickel concentration in the samples. The saturation magnetization (MS) and blocking temperature (Tb) of the system show increasing trends with increasing cobalt concentration in the nanoparticles.