Facile Synthesis and Characterization of Fe/FeS Nanoparticles for Environmental Applications

Abstract

Multicomponent nanoparticles containing two or more different types of functionalities show unique physical and chemical properties, leading to significantly enhanced performance. In this study, we have developed a new one-pot method to prepare Fe/FeS nanoparticles using dithionite at room temperature. The FeS precipitates on the Fe surface are formed by the interaction between dissolved iron species and hydrogen sulfide, one of the decomposition products of dithionite in solution. The resulting Fe/FeS nanoparticles have high surface area, good electrical conductivity, and strong magnetic responsivity. In addition, the Fe/FeS shows a much higher reactivity toward contaminants than the pure Fe nanoparticles. The above synthesized nanoparticles are successfully applied for the rapid removal of trichloroethylene (TCE) from water. The study reveals that Fe/FeS nanoparticles are a promising candidate for the efficient removal of pollutants.

Magnetic sulfide-modified nanoscale zerovalent iron (S-nZVI) for dissolved metal ion removal

“…nZVI and S-nZVI were synthesized using the method described by Kim et al (2011). Briefly, 250 ml 7.6 g sodium borohydride with different amounts of dithionite (0, 0.125, 0.25, 0.5, 0.75, and 1 g) were separately introduced into 250 ml FeCl 3 solution (4.9 g) via titration (titration rate~1 L/h), to achieve S/Fe molar ratios of 0 (or nZVI), 0.035, 0.07, 0.14, 0.21, and 0.28.…”

“…Furthermore, metal sulfides are very stable as indicated by their low solubility product constant (Table S1), which means immobilized metals are not likely to be released into water again. Recent studies indicate that S-nZVI has a higher surface area and reactivity, but lower isoelectric point (IEP) than nZVI (Kim et al, 2011(Kim et al, , 2013a. These characteristics, together with a simple synthesis process (titrating a mixture of sodium borohydride and dithionite into ferric solution) (Kim et al, 2011(Kim et al, , 2013a, make S-nZVI an ideal material for heavy metal removal from water bodies.…”

“…S-nZVI is generally conceived as an Fe 0 core with FeS shell (Kim et al, 2011), but when the mixture of sodium borohydride and dithionite is added into ferric solution, reduction (Eqs. (1) and (2)) (Li and Zhang, 2006), selfdecomposition of dithionite (Eqs.…”

Biosynthesis of Multicomponent Nanoparticles with Extract of Mortiño (Vaccinium floribundum Kunth) Berry: Application on Heavy Metals Removal from Water and Immobilization in Soils

“…Gagnepain and Roques-Carmes exploited this technique to characterize the uniformity of surfaces for pro les in two dimensions, with Ds falling within a range between 1 and 2, in which 1 corresponds to a smooth surface and 2 to a highly rough surface [20]. Recently, in the fabrication of Fe/FeS nanoparticles was evidenced an enhancement in roughness of the particles' surfaces [7,8]. Evidently, a high roughness favors the reactivity of the nanoparticle due to the increase of its surface area, thus promoting the formation of more reactive sites [7,21].…”

“…e inclusion of two or more components can add supplementary functionality to the particles, such as antimicrobial activity, chemical-mechanical polishing [5], magnetic capability [6], and others. Among the MCNPs prepared up to now, Fe/FeS nanoparticles were formed by the interaction between dissolved iron species and hydrogen sulfide using sodium borohydride (NaBH 4 ) as a reducing agent at room temperature [7]. Using this procedure of fabrication, the FeS precipitates on the Fe 0 surface.…”