In ³⁺ -substituted nickel-zinc spinel ferrites: synthesis and evaluation of thermal, structural, morphological, magnetic and catalytic application for synthesis of acridine-1,8-dione derivatives

Nanocrystalline Ni0.4Zn0.6Fe2−xInxO4 spinel ferrites were synthesized by the oxalate precursor route. Thermogravimetric analysis of the oxalate precursor revealed a multistep decomposition process and the kinetic parameters were determined using the Coats–Redfern model. Oxalate precursors were calcined at 773 K. EDAX results confirmed that the elements were observed consistent with the expected stoichiometry. Rietveld refinement of XRD confirmed the single-phase cubic spinel structure, which was devoid of any impurity phases. FTIR spectra displayed two characteristic metal–oxygen vibrational modes associated with tetrahedral and octahedral sites. FESEM and HRTEM micrographs showed uniformly distributed nanosized grains with a porous architecture. Magnetic measurements indicated a decline in saturation magnetization and magnetic moment with In3+ addition. Among the investigated compositions, the x = 0.10 sample exhibited the highest BET surface area, pore volume, and C-constant. Acridine 1,8-dione derivatives were efficiently synthesized by a one-pot, three-component method using a magnetically separable and reusable catalyst In3+-doped Ni–Zn ferrite.