Iron-Nickel Alloy with Starfish-like Shape and Its Unique Magnetic Properties: Effect of Reaction Volume and Metal Concentration on the Synthesized Alloy.

Norhan Nady,Marwa A A Mohamed,Sherif H Kandil,Noha Salem

doi:10.3390/nano11113034

Abstract

Iron-nickel alloy is an example of bimetallic nanostructures magnetic alloy, which receives intensive and significant attention in recent years due to its desirable superior ferromagnetic and mechanical characteristics. In this work, a unique starfish-like shape of an iron-nickel alloy with unique magnetic properties was presented using a simple, effective, high purity, and low-cost chemical reduction. There is no report on the synthesis of such novel shape without complex precursors and/or surfactants that increase production costs and introduce impurities, so far. The synthesis of five magnetic iron-nickel alloys with varying iron to nickel molar ratios (10–50% Fe) was undertaken by simultaneously reducing Fe(II) and Ni(II) solution using hydrazine hydrate as a reducing agent in strong alkaline media for 15 min at 95–98 °C. The effect of reaction volume and total metal concentration on the properties of the synthesized alloys was studied. Alloy morphology, chemical composition, crystal structure, thermal stability, and magnetic properties of synthesized iron-nickel alloys were characterized by means of SEM, TEM, EDX, XRD, DSC and VSM. ImageJ software was used to calculate the size of the synthesized alloys. A deviation from Vegard’s law was recorded for iron molar ration higher than 30%., in which superstructure phase of FeNi3 was formed and the presence of defects in it, as well as the dimensional effects of nanocrystals. The saturation magnetization (Ms), coercivity (Hc), retentivity (Mr), and squareness are strongly affected by the molar ratio of iron and nickel and reaction volume as well as the total metal concentration.

Highlights

In recent years, nanomaterials have begun to revolutionize the world as they provide new dimensions for research and development
One of the important magnetic properties is coercivity (Hc), which is a measure of the ability of a ferromagnetic material to keep its magnetization when
Ni90) and the low purity of the prepared alloys, (6) there are no sufficient studies to prestudies to prepare high magnetic properties of Fe10 Ni90 using simple, inexpensive and pare high magnetic properties of Fe10 Ni90 using simple, inexpensive and easy-to-control easy-to-control methods such as simple chemical reduction, and (7) there are no studies methods such as simple chemical reduction, and (7) there are no studies documenting the documenting the study of the effect of the volume of the reaction solution on the purity study of the effect of the volume of the reaction solution on the purity and properties of and properties of iron and nickel alloys

Summary

Introduction

Nanomaterials have begun to revolutionize the world as they provide new dimensions for research and development. Nanoparticles (NPs) are ultrafine particles with lengths ranging from 1 to 100 nm at least one dimension. They have a high surface-area-to-volume ratio, which enables them to exhibit different physical and chemical properties such as reactivity, versatility, and strength than their bulk counterparts [1,2]. Magnetic nanoparticles (MNPs) attracted increased attention due to their unique physicochemical and magnetic properties [3,4]. MNPs are potentially employed in many applications such as biomedicine [2,5], environmental remediation [1,4], catalysis [6,7], magnetic resonance imaging [8,9], data storage [10,11], sensors [12,13], electromagnetic shielding [14], and absorbing materials [15], etc. One of the important magnetic properties is coercivity (Hc), which is a measure of the ability of a ferromagnetic material to keep its magnetization (i.e., without being demagnetized) when

Methods

Discussion

Conclusion