Combined Layer-by-Layer/Hydrothermal Synthesis of Fe3O4@MIL-100(Fe) for Ofloxacin Adsorption from Environmental Waters

Abstract

A simple not solvent and time consuming Fe3O4@MIL-100(Fe), synthesized in the presence of a small amount of magnetite (Fe3O4) nanoparticles (27.3 wt%), is here presented and discussed. Layer-by-layer alone (20 shell), and combined layer-by-layer (5 shell)/reflux or /hydrothermal synthetic procedures were compared. The last approach (Fe3O4@MIL-100_H sample) is suitable (i) to obtain rounded-shaped nanoparticles (200–400 nm diameter) of magnetite core and MIL-100(Fe) shell; (ii) to reduce the solvent and time consumption (the layer-by-layer procedure is applied only 5 times); (iii) to give the highest MIL-100(Fe) amount in the composite (72.7 vs. 18.5 wt% in the layer-by-layer alone); (iv) to obtain a high surface area of 3546 m2 g−1. The MIL-100(Fe) sample was also synthesized and both materials were tested for the absorption of Ofloxacin antibiotic (OFL). Langmuir model well describes OFL adsorption on Fe3O4@MIL-100_H, indicating an even higher adsorption capacity (218 ± 7 mg g−1) with respect to MIL-100 (123 ± 5 mg g−1). Chemisorption regulates the kinetic process on both the composite materials. Fe3O4@MIL-100_H performance was then verified for OFL removal at µg per liter in tap and river waters, and compared with MIL-100. Its relevant and higher adsorption efficiency and the magnetic behavior make it an excellent candidate for environmental depollution.

Synthesis of MIL-Modified Fe3O4 Magnetic Nanoparticles for Enhancing Uptake and Efficiency of Temozolomide in Glioblastoma Treatment

“…Recently, Metal-Organic Frameworks (MOFs) coordination polymers consisting of metal nodes and polydentate organic linkers organized in open porous structures [ 18 , 19 ] and, among them, MILs (Materials Institute Lavoiser) an MOF subclass constituted by trivalent transition metals and bi- or tri-carboxylic ligands, showed great potentiality for biomedical applications either as pure crystals or as composite materials, because of their biocompatibility and capability of loading molecules in their porous structure [ 20 , 21 , 22 , 23 , 24 ]. Moreover, some paper reported on the possibility of combining magnetic nanoparticles with MILs structures either as composite materials made of MILs crystals decorated or loaded with magnetic Fe 3 O 4 nanoparticles [ 25 , 26 , 27 , 28 ] or core-shell systems in which an Fe 3 O 4 core is covered with a MIL shell [ 29 , 30 , 31 , 32 , 33 , 34 , 35 ]. In both cases typically particles sizes ranged from 200–500 nm.…”

Experimental and Theoretical Study of Sorption Capacity of Hexagonal Boron Nitride Nanoparticles: Implication for Wastewater Purification from Antibiotics

“…For example, graphene-based nanomaterials were utilized to remove antibiotics [18][19][20], which are adsorbed on the material surfaces due to π-π-, electrostatic or hydrophobic interactions, as well as the formation of hydrogen bonds. Highly efficient antibiotic sorption was also observed when using highly porous, surface-active, and structurally stable silica-based materials [21,22], metal oxide nanoparticles [15,23,24], and metal-organic frameworks [25,26].…”

The Use of a Novel Graphitic Carbon Nitride/Cerium Dioxide (g-C3N4/CeO2) Nanocomposites for the Ofloxacin Removal by Photocatalytic Degradation in Pharmaceutical Industry Wastewaters and the Evaluation of Microtox (Aliivibrio fischeri) and Daphnia magna Acute Toxicity Assays

“…Highly efficient antibiotic sorption was also observed when using highly porous, surface-active, and structurally stable silicabased materials, metal oxide NPs, and metal-organic frameworks. The photocatalysts, which mainly rely on the production of highly oxidizing species such as hydroxyl radical (OH • ) and superoxide anion radical (O 2 − • ), have been considered an effective approach for the degradation of antibiotics in water [86][87][88][89][90][91][92][93][94][95][96][97][98][99][100][101][102][103].…”