Fabrication, characterization, and magnetic behavior of porous ZnFe2O4 hollow microspheres

Abstract

Porous ZnFe 2 O 4 hollow microspheres with a diameter of about 100-210 nm were successfully prepared by simple template-free hydrothermal route in ethylene glycol (EG) solution. The formation mechanism and properties have been also demonstrated. The structural, morphological, and magnetic properties of ZnFe 2 O 4 hollow microspheres were investigated by means of X-ray powder diffraction (XRD), field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and physical properties measurements system. The surface area was determined using the BET method. XRD and IR analyses confirm the cubic spinel phase of ZnFe 2 O 4 hollow microspheres. Every magnetic microsphere is made up of many ultrafine ZnFe 2 O 4 nanoparticles with porous structure. The as-prepared porous magnetic hollow spheres have higher surface area and excellent magnetic properties at room temperature.

Arabic Gum-Grafted-Hydrolyzed Polyacrylonitrile@ZnFe2O4 as a Magnetic Adsorbent for Remediation of Levofloxacin Antibiotic from Aqueous Solutions

“…The BET surface area of AG- g -PAN@ZnFe 2 O 4 was measured at 6.58 m 2 /g which was higher than that for AG- g -HPAN (0.080 m 2 /g). The reason for this observation is the presence of zinc ferrite nanosphere in the polymer matrix of AG- g -HPAN since the reported value of BET surface area for zinc ferrite nanosphere which was prepared by a similar procedure was 42 m 2 /g …”

“…In the temperature range 50–200 °C, water evaporation resulted in a slight weight loss (2%) in the TGA thermogram of ZnFe 2 O 4 . In addition, the 8% weight loss at 400 °C might be explained by dehydroxylation and decomposition of carbanions precursor for ferrite production . Furthermore, due to ferrite crystallization, weight loss remained exceedingly gradual up to 600 °C, resulting in ZnFe 2 O 4 ’s extraordinary thermal stability with a char generation of 90% at 800 °C.…”

Effects of Various Sintering Conditions on the Structural and Magnetic Properties of Zinc Ferrite (ZnFe2O4)

“…The functional groups of ZnFe 2 O 4 sintered for various times are similar except in the case of the sample sintered for 2.5 h, whose spectrum shows additional peaks in the 0-500 cm −1 range. The main peaks of ZnFe 2 O 4 are observed in the range 400-600 cm −1 , representing Fe-O and Zn-O bonds 10,16,17 involved in metal-oxygen vibration stretching in octahedral and tetrahedral sites 18,19 . The strong absorption peak at ~1508 cm −1 corresponds to the C=C stretching vibration 20 and indicates the presence of surface hydroxyl groups 19 or moisture 18 .…”

“…The main peaks of ZnFe 2 O 4 are observed in the range 400-600 cm −1 , representing Fe-O and Zn-O bonds 10,16,17 involved in metal-oxygen vibration stretching in octahedral and tetrahedral sites 18,19 . The strong absorption peak at ~1508 cm −1 corresponds to the C=C stretching vibration 20 and indicates the presence of surface hydroxyl groups 19 or moisture 18 . The peak at ~2300 cm −1 represents stretching vibrations of ether groups with C=O and N-H or O-H 21 either the peak corresponding to the O-H (H 2 O bending mode) group indicates the conversion of water to steam in the ZnFe 2 O 4 nanoparticles 17,18,20 .…”

Spinel ferrite (AFe2O4)-based heterostructured designs for lithium-ion battery, environmental monitoring, and biomedical applications

“…The use of some basic approaches (solvothermal and hydrothermal methods) combined with innovative processes arising from ionic liquid and polymer support in the reaction mixture (chitosan (CS) and ethylene glycol) can also provide many promising results. [66][67][68] Indeed, these polymers act as substances that can limit the core growth of SFNs during preparation and help stabilize SFNs via steric repulsion when NPs are dispersed in aqueous media. S. Briceño et al 69 reported that the solvothermal synthesis of cobalt ferrite with the support of CS resulted in the best yield of hollow spheres with a narrow size distribution.…”