Magnetic SiO 2 @CoFe 2 O 4 nanoparticles decorated on graphene oxide as efficient adsorbents for the removal of anionic pollutants from water

Abstract

In this study, magnetic nanocomposites viz. SiO 2 @CoFe 2 O 4 nanoparticles decorated on graphene oxide were synthesized using solvothermal and sol-gel processes. The prepared nanocomposite materials were used as magnetic adsorbents for the removal of organic and inorganic pollutants (acid black 1 dye and Cr(VI) ions as model pollutants) from aqueous solution. The structure, morphology and other physico-chemical properties of nanocomposites were characterized by X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), high resolutiontransmission electron microscopy (HR-TEM), vibrating sample magnetometer (VSM), X-ray Photo spectroscopy (XPS), zeta potential and Fourier infrared (FT-IR) spectroscopy. Batch mode adsorption studies were conducted with the prepared nanocomposites to determine the maximum adsorption capacity of acid black 1 dye and Cr(VI) ions as a function of contact time, pH, adsorbent dosage and initial adsorbate concentrations. Different kinetic and isotherm models were tested to describe and elucidate the adsorption mechanisms. Based on the experimental results obtained, the synthesized materials proved to exhibit considerable potential for the removal of acid black 1 and Cr(VI) ions from aqueous solution.

Dopamine Loaded SiO2 Coated Fe3O4 Magnetic Nanoparticles: A New Anticancer Agent in pH‐Dependent Drug Delivery

“…In both of the blue and pink spectra, the bands observed at 1631 cm −1 and broad band around 3600–3200 cm −1 correspond to the O–H bond bending vibration and stretching mode of water chemisorbed on MNP's surface . The peaks are assigned with the reported work . For DA loaded particles we see some new peaks with two broad bands at ∼3500 cm −1 are assigned to the stretching of N−H and O−H, and two peaks observed at 2800 cm −1 are may be due to the secondary amines.…”

Synthesis and Properties of Nanosized Stoichiometric Cobalt Ferrite Spinel

“…Due to its magnetic properties, CoFe 2 O 4 nanoparticles may be employed in catalysts [1,2], cathode electrocatalyst of microbial fuel cells [3], or in various functional composite materials [4,5], including advanced adsorbents, for the removal of anionic pollutants from water [6]. Cobalt ferrite has been also considered as a good candidate for biomedical applications [7,8,9], especially for hyperthermia treatment, because of its high magneto-crystalline anisotropy [7].…”

“…A usual synthetic technique for preparation of magnetic CoFe 2 O 4 nanoparticles is the co-precipitation method [1,2,3,4,5,6,7,8,9,10,11,12,13], but also hydrothermal [14,15,16,17], sol-gel auto-combustion [18,19], and microwave assisted [20,21] methods can be applied.…”

A review on adsorptive remediation of Cr (VI) by magnetic iron oxides and their modified forms

“…The surface hydroxyl groups and magnetic cyclodextrin-chitosan present in the adsorbent are homogeneously distributed on the surface of graphene oxide and the adsorption process involves the following steps. (i) Negatively charged Cr (VI) species get attracted by protonated amine groups of the adsorbent in acidic medium due to electrostatic attraction [47]. (ii) In acidic medium, Cr (VI) is partial reduced to Cr (III) with the help of π -electrons present on the carbocyclic six membered ring of cyclodextrinchitosan modified graphene oxide.…”