Comparative Study of Synthesis Methods to Prepare New Functionalized Adsorbent Materials Based on MNPs–GO Coupling

Abstract

In this work, the synthesis of new adsorbent nanomaterials based on the coupling of magnetic nanoparticles and graphene oxide (MNPs–GO) was addressed. Separately, MNPs and GO have adsorbent properties of great interest, but their use involves certain difficulties. The coupling seeks compensation for their disadvantages, while maintaining their excellent properties. Three different routes to synthesize coupled MNPs–GO were studied and are compared in this work. The three synthesized materials were functionalized with chelating groups: [1,5-bis (di-2-pyridyl) methylene] thiocarbonohydrazide (DPTH) and [1,5-bis(2-pyridyl)3-sulfophenylmethylene] thiocarbonohydrazide (PSTH). The new adsorbent nanomaterials were characterized adequately. Moreover, their capacities of adsorption toward heavy and noble metals were determined, in order to apply them as extractants in magnetic solid-phase extraction to preconcentrate metals in environmental samples. The results showed that one of the routes provided nanomaterials with better adsorbent characteristics and higher yields of functionalization.

New Magnetic Chelating Sorbent for Chromium Speciation by Magnetic Solid Phase Extraction On-Line with Inductively Coupled Plasma Optical Emission Spectrometry

“…The synthesis of M@GO was reported in the patent [18,20]. The obtained M@GO was functionalized in several steps.…”

“…In SM3, a double peak appears for N(1s). The peak at 399 eV corresponds to the aromatic nitrogen [18] while the peak at 402 eV is due to ammonium salts [18] NH 4…”

“…As sorbents, modified or functionalized magnetic nanoparticles (MNPs) can be used, overall, for applications in the fields of trace metal ion preconcentration and separation. Superficially modified MNPs with, such as silica, alumina, carbon nanotubes (CNTs), graphene oxide (GO), polymer, surfactant, analytical reagent surfactants etc., can be used to improve the coating efficiency and stability [17][18][19].…”

Magnetic graphene oxide as a valuable material for the speciation of trace elements

“…Other authors synthesise MNPs by coprecipitation on the GO and then functionalize via the carboxyl groups of the GO films [33]. A third way to synthesise the MGO is a combination of the two previous routes, achieving a higher functionalization rate by the introduction of GP into the MNPs and GO, and by the incorporation of chemical anchors between them [34].…”

A Molecularly Imprinted Polypyrrole/GO@Fe3O4 Nanocomposite Modified Impedimetric Sensor for the Routine Monitoring of Lysozyme

“…Despite the presence of the π-π domain, a hydrophilic character is provided, resulting in high adsorption capacity for the retention and preconcentration of polar species and metal ions. In recent years, researchers have proposed the coupling of Fe 3 O 4 -NPs and GO, combining their biocompatibility, degradability, physiological and chemical stability, and excellent adsorbent properties for the preparation of decorated graphene oxide (GO@Fe 3 O 4 ) [ 28 , 29 ]. For this reason, in this work, GO@Fe 3 O 4 nanocomposite was selected, presenting amine groups and oxygen-containing functional groups that are compatible to interact with the template through dipole interactions and hydrogen bonds, and used to produce microporous polypyrrole (MIPPy/GO@Fe 3 O 4 ) imprinted with lysozyme.…”