Amino acid-assisted synthesis of superparamagnetic CoFe2O4 nanostructures for the selective adsorption of organic dyes

Abstract

We report a facile synthesis of superparamagnetic CoFe 2 O 4 nanostructures with the assistance of an amino acid (lysine). Monodisperse CoFe 2 O 4 nanospheres and nanoparticles were obtained by adjusting the synthesis parameters (such as the molar ratio of reactants and the solvent). The samples were characterized through scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, and Fourier-transform infrared spectroscopy. The magnetic property and measured zeta potential shows that both CoFe 2 O 4 nanostructures were superparamagnetic and positively charged. The adsorption performance of the CoFe 2 O 4 nanostructures was evaluated using different dyes, namely, methylene blue, Congo red, Acid Blue 80, methyl orange, rhodamine B, and Cationic red X-GTL, as models. The results show that CoFe 2 O 4 nanospheres consisting of nanoparticles display high adsorption performance on methylene blue, methyl orange, and Congo red, whereas CoFe 2 O 4 nanoparticles prefer adsorbing rhodamine B and Congo red. Therefore, the tunable synthesis of superparamagnetic CoFe 2 O 4 nanostructures provides promising applications for the selective and highly efficient removal of various organic contaminants from industrial effluents.

Related magnetic properties of CoFe2O4 cobalt ferrite particles synthesised by the polyol method with NaBH4 and heat treatment: new micro and nanoscale structures

“…There is no doubt that Pt/CoFe 2 O 4 particles with grain and grain boundary will become promising magnetic catalytic materials [4,15] properties of between superparamagnetism without magnetic hysteresis, paramagnetism or antiferromagnetism, and ferrimagnetism or ferromagnetism [17][18][19][20][21][22][23]. It turned out that this unique ferrimagnetic characterization was due to the existence of various magnetic small and large multidomains from grain and grain boundary configurations of various as-prepared CoFe 2 O 4 materials in heat treatment process used [10].…”

“…In particular, Fe 2 Although various commercial Fe-, Ni-, Co-based ferrite powders were produced in decades ago, they enabled large potential of modern applications and technologies of magnetic recording media, various lithiumion batteries (LIBs) and fuel cells (FCs) for sustainable development of energy and environment [2,3,15,16,27,32,33]. In recent years, Co-, Ni-, and Fe-based ferrites with inexpensive costs have been of commercial importance, such as microwave components and defense [17][18][19][20][21][22][23]. In CoFe 2 O 4 ferrites, e.g.…”

“…system). AB 2 O 4 , which resulted in different results of paramagnetic or ferromagnetic or ferrimagnetic properties of hysteresis loops in various works[17][18][19][20][21][22][23][24][25]27,28]. There are the relative distribution of magnetic Fe ions on Tet-A and Oct-B sites when the contents of Co ions were integrated into CoFe 2 O 4 .…”

Fixed-bed adsorption of methylene blue by rice husk ash and rice husk/CoFe2O4nanocomposite

“…The magnetic and catalytic abilities of ferrite make it potential to enhance the treating efficiency and also make the adsorbents recyclable [29]. Dong et al [30] found that CoFe 2 O 4 nanosphere consisting of nanoparticles display high adsorption performance on organic dyes. Ai et al [31] combined the AC with CoFe 2 O 4 to create a composite which could be used as a promising and effective adsorbent for the removal of malachite green from water.…”

Solvothermal synthesis of magnetic CoFe2O4/rGO nanocomposites for highly efficient dye removal in wastewater

“…Cobalt ferrite (CoFe 2 O 4 ) nanocrystals with spinel structure have attracted signicant attention for environmental remediation because of their outstanding properties, such as high saturation magnetization, and size-and shape-dependent magnetic behaviour. 27 Although some studies have reported the preparation and adsorption properties of CoFe 2 O 4 /graphene nanocomposites, the trivial process of preparation, 28 slow removal rate, 29 and low adsorption capacities 30,31 hinder their applications in industrial wastewater treatment, which still remains a challenging task. In addition, Chen 32 et al reported a one-step method to prepare CoFe 2 O 4 -rGO by ball-milling, and the as-prepared CoFe 2 O 4 -rGO could be used for organic dye removal by photocatalytic degradation.…”