Magnetothermally-responsive nanocarriers using confined phosphorylated halloysite nanoreactor for in situ iron oxide nanoparticle synthesis: A MW-assisted solvothermal approach

Year: 2021

Authors: Gonzalez-Rivera Jose; Spepi Alessio; Ferrari Carlo; Tovar-Rodriguez Jorge; Fantechi Elvira; Pineider Francesco; Antonio Vera-Ramirez Marco; Tine Maria Rosaria; Duce Celia

Autors Affiliation: Department of Chemistry and Industrial Chemistry, University of Pisa, Via G. Moruzzi 13, Pisa, 56124, Italy; National Research Council of Italy (C.N.R.), National Institute of Optics, (INO) – UOS Pisa, Via G. Moruzzi 1, Pisa, 56124, Italy; Department of Chemistry “”Ugo Schiff””, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy; Department of Chemistry, UAM-I, 55534, Myxico D.F., 09340, Mexico

Abstract: A family of easily recoverable magnetic and thermally responsive composite materials, with nanoscale dimensions, were synthesized by a rapid and simple solvothermal approach. The synthesis was thermally activated, accelerated, and controlled using a coaxial antenna to directly apply the microwave energy inside the solvothermal reactor. The composite materials were made up by a confined phosphorylated nanoreactor, namely halloysite nanotubes grafted on the inner lumen with phosphoric acid (HNTs-(H+-PO4)), that promoted the urea hydrolysis thus favoring the formation of a local alkaline environment to catalyze the homogeneous in situ precipitation of superparamagnetic iron oxide nanoparticles (IONs) selectively on their inner or outer surface. Two new MW-assisted solvothermal methodologies were used: 1) in the first the solvent is directly loaded into the MW-assisted reactor together with HNTs-(H+-PO4) mechanically preloaded with iron chloride and urea in the lumen 2) in the second the synthesis is preceded by a further pre-functionalization step of the iron salt with clove essential oil (EO) as a green functionalization agent. Structural, morphological, textural, and magnetic properties were assessed by TEM, N2 physisorption, TG-FTIR, ICP, XRD, magnetic and magnetic hyperthermia measurements. The MW-assisted solvothermal deposition of IONs was fully controlled using the phosphorylated


Volume: 635      Pages from: 128116-1  to: 128116-11

KeyWords: Halloysite nanotubes; Magnetic nanocomposites; Microwaves; Selective functionalization; Iron oxide nanoparticles
DOI: 10.1016/j.colsurfa.2021.128116