Mixed Iron−Manganese Oxide Nanoparticles

Abstract

Designing nanoparticles for practical applications requires knowledge and control of how their desired properties relate to their composition and structure. Here, we present a detailed systematic study of mixed iron-manganese oxide nanoparticles, showing that ultrasonication provides the high-energy reaction conditions required for complete atomic level mixing of Fe(III) and Mn(III) when amorphous Fe 2 O 3 nanoparticles are irradiated in the presence of Mn 2 (CO) 10 in ambient atmosphere. X-ray diffraction (XRD) results reveal that the crystal structure of manganese iron mixed oxide nanoparticles changes from spinel to bixbyite with increasing of Mn(III) content. The results of room-temperature magnetization curves are consistent with the XRD patterns and spin density from electron paramagnetic resonance measurements, showing samples converting from superparamagnetic to antiferromagnetic, when the crystal structures of these samples transform from spinel to bixbyite.

Porous magnetic manganese oxide nanostructures: Synthesis and their application in water treatment

“…According to line S2 in Fig. 1, all the diffraction peaks can be indexed to the mixtures form of birnessite (JCPDS 23-1046) [22], tetragonal hausmannite structure (space group I41/amd) of Mn 3 O 4 with lattice constants of a = b = 5.762 Å, and c = 9.470 Å (JCPDS 24-0734) [9,37], and bixbyite (space group pcbb/61) of Mn 2 O 3 with lattice constants of a = 9.416 Å, b = 9.424 Å, and c = 9.405 Å (JCPDS 24-0508) [38][39][40]. All the XRD results show the components of the structures and potential chemical changes take place in both the Baeyer reaction and thermal treatment.…”

Synthesis and characterization of chitosan coating of NiFe2O4 nanoparticles for biomedical applications

“…It is of a particular ferromagnetism quality that originates from the magnetic moment of antiparallel spins [9]. Several methods can be employed for the synthesis of (NiFe 2 O 4 ) nanoparticles; they include: heat treatment [10], co-precipitation [11], chemical methods [12], sonochemical [13], sol-gel [14], and thermal decomposition [15,16]. Nevertheless, the strong dipoledipole interaction causes the tendency of these NiFe 2 O 4 nanoparticles to aggregate; hence, it is required to modify their surface with biocompatible and biodegradable polymers.…”

Manganese associated nanoparticles agglomerate of iron(III) oxide: Synthesis, characterization and arsenic(III) sorption behavior with mechanism

“…Mixed oxide of iron-manganese nanoparticle has gained special attention in various technological fields of material science for the temperature dependent antiferromagnetic and superparamagnetic behaviors [1], and as a negative temperature coefficient material [2]. Recent applications of nanometer scale materials for environmental remediation have encouraged in evaluating the efficiency of arsenic sorption.…”