Estimation of the cation distribution in Co3-XNiXO4 (0 ≤ X ≤ 1.28) synthesized from crystallized Co1-YNiY(OH)2 (X = 3Y) prepared by the uniform precipitation method

Abstract

The crystal structure and magnetic properties of Co3-XNiXO4 (CNO) (0 ≤ X ≤ 1.28) powder samples produced from uniformly precipitated Co1-YNiY(OH)2 (X = 3Y) precursors were investigated herein. The X-ray diffraction analysis of the samples showed that they had a cubic spinel structure when 0 ≤ X ≤ 1.28. With increasing nickel content (X), the saturation magnetization per formula unit MS at 5 K increased from 0 μB at X = 0 to 0.97 μB at X = 0.74, and subsequently decreased to 0.78 μB at X = 1.28. When X ≥ 0.23, the magnetic transition temperature increased from 35 K at X = 0.23 to 290 K at X = 1.28. The distribution of the cations in the crystal was estimated from the lattice parameters and saturation magnetization data, MS-Exp, measured at 5 K. The estimated compositional dependence of the saturation magnetization MS-Fit was consistent with the observed trend in the MS-Exp.