The Effect of Temperature on Synthesis and Stability of Superparamagnetic Maghemite Nanoparticles Suspension

Abstract

Maghemite (γ-Fe 2 O 3 ) nanoparticles have been synthesized using chemical co-precipitation at a different temperature. Characterizations of the sample were performed by X-ray diffraction (XRD), transmission electron microscopy (TEM), alternating gradient magnetometry (AGM) and thermogravimetryanalysis (TGA). The stability of the maghemite nanoparticles suspension was studied at different pH and time of storage by dynamic light scattering (DLS) and zeta potential measurements. The XRD patterns confirmed that the particles were maghemite. TEM observation showed that the particles have spherical morphology with narrow particle size distribution. The particles showed superparamagnetic behavior with good thermal stability. The increasing of temperature in the synthesis of maghemite nanoparticles produced smaller size particles, lower magnetization, better thermal stability and more stable maghemite nanoparticle suspension.

Intra-Organ Delivery of Nanotherapeutics for Organ Transplantation

“…For example, increasing the reaction temperature in the synthesis of cobalt ferrite NPs (CoFe 2 O 4 –NPs) augments their size, increases their saturation magnetization, and results in the formation of an equiaxial-shaped, single-phase cubic spinel structure . On the other hand, increasing the reaction temperature decreases the size of maghemite NPs (γ-Fe 2 O 3 -NPs), lowers their magnetization, and improves their stability . Increasing the reaction temperature boosts the aggregation of gold NPs (Au-NPs) .…”

“…179 On the other hand, increasing the reaction temperature decreases the size of maghemite NPs (γ-Fe 2 O 3 -NPs), lowers their magnetization, and improves their stability. 180 Increasing the reaction temperature boosts the aggregation of gold NPs (Au-NPs). 181 Finally, intermediate reaction temperatures have been demonstrated to produce smaller silver NPs (Ag-NPs) with narrow size distribution.…”

A study on the preparation and characterization of maghemite (γ-Fe2O3) particles from iron-containing waste materials

“…The first degradation stages from around 36−198°C, with a mass loss of 8.72%, are related mainly to desorption of moisture, and loss of water physically adsorbed on the surface of the materials [47]. Second weight loss (13.2 %) occurs between 199°C to 329°C temperature, which corresponds to the chemisorb of water and is also supported by a sharp DTG peak at 252°C [52,53]. The third dehydration step (weight loss of 9.03%) takes place between 330°C to 748°C, which can be attributed to the breakage of the chemical bonding between iron and the hydroxyl group.…”

Synthesis of Maghemite Pigment (γ-Fe2O3) from Lathe Waste Using Precipitation-Calcination Route

“…Maghemite pigment is a widely useful used in coating, construction materials [6] [7] and other application, because have advantage including chemical stability, biocompatible, nontoxic, biodegradable, stable, and resistance at high temperature [2] [8]. Many methods have been developed in synthesizing maghemite, such as hydrothermal [9], microwave-assisted reduction [10], ferrihydrite reduction [11], reductionprecipitation method [12], co-precipitation [13,14] precipitation-calcination [7][15], thermal decomposition [16], and sintering treatment [17]. Precipitation-calcination method is reproducible, simple, low cost, and large yield quantity of product [13] [14].…”

“…Many methods have been developed in synthesizing maghemite, such as hydrothermal [9], microwave-assisted reduction [10], ferrihydrite reduction [11], reductionprecipitation method [12], co-precipitation [13,14] precipitation-calcination [7][15], thermal decomposition [16], and sintering treatment [17]. Precipitation-calcination method is reproducible, simple, low cost, and large yield quantity of product [13] [14]. In the calcination route, the structure, phase, particle size, and morphology of iron oxide depend on temperature [18][19] [20][21].…”