Structural, magnetic, and electronic structure of the nanostructured (CoMn)50Ni50 powders used in dye discoloration via a heterogeneous Fenton-like process

Abstract

Nanocrystalline (CoMn)₅₀Ni₅₀ powders were prepared by the mechanical alloying process in a high-energy planetary ball mill under an argon atmosphere. Morphology, structure, microstructure, and magnetic properties were investigated using scanning electron microscopy, X-ray diffraction, and magnetometry. The (CoMn)₅₀Ni₅₀ powders exhibit a highly disordered solid solution with a lattice parameter of a = 0.3542(4) nm, and undergo a ferromagnetic to paramagnetic transition at a Curie temperature of about 700 K. Different magnetic parameters were extracted from the approach to magnetic saturation. The electronic structure of the ferromagnetic powders was performed by the self-consistent ab initio calculations based on the Korringa–Kohn–Rostocker (KKR) method combined with the Coherent Potential Approximation (CPA). The total DOS is mainly due to the 3d-like states of the constituent elements Co, Mn, and Ni. The powders were tested in the discoloration reaction of Methylene Blue under different operation conditions via a heterogeneous Fenton-like process.