Rare-earth ions as a key influencer on the magnetic, spectroscopic and elastic properties of ErγZn0.2Co0.8Fe2−γO4 nanoparticles

Highlights: • Er_γZn_0.2Co_0.8Fe_2-γO₄ nanoparticles (E-ZCFNs) prepared by citrates sol-gel. • The structural, optical, elastic, and magnetic properties of the E-ZCFNs examined. • The E-ZCFNs are semiconductor candidate for photosensing & medical applications. • The E-ZCFNs have high both elastic moduli and wave elastic velocities at Er ≤0.14. • Er ions content effects deeply on the properties of ZCFNs. -- Abstract: Rare-earth ions substitution into spinel nanoscale structure can alter its properties. So, this study delineates the microstructure-property relationship due to the extraordinary role of doping erbium in inverse zinc-cobalt ferrite nanoparticles (E-ZCFNs). The studied compounds were synthesized via the citrates sol-gel auto-combustion method and the effect of varying erbium concentration on their optical, mechanical, and magnetic properties has been evaluated. The microstructure of the E-ZCFNs compounds indicates that the spinel structure phase and orthoferrite phase can coexist in the compounds with erbium ions content ≈ 0.21. The compounds doped with erbium ions have better mechanical and microstructural properties at γ ≤ 0.14. The investigated compounds have low average particles size (12.58–17.35) nm and high Curie temperature (695 and 723) K. Our study finds that upon doping substitution, decreasing both the molar magnetic susceptibility and the effective magnetic moment and their magnitudes are dependent on the cationic distances and cations distribution in the studied compounds. The E-ZCFNs compounds exhibit a distinctive optical behavior, as they possess two absorption peaks in the Uv range and two values for both the optical energy gap and the refractive index.