Sponge-supported synthesis of colloidal selenium nanospheres

Abstract

With increasing biomedical and engineering applications of selenium nanospheres (SeNS), new efficient methods are needed for the synthesis and long-term preservation of these nanomaterials. Currently, SeNS are mostly produced through the biosynthesis route using microorganisms or by using wet chemical reduction, both of which have several limitations in terms of nanoparticle size, yield, production time and long-term stability of the nanoparticles. Here, we introduce a novel approach for rapid synthesis and long-term preservation of SeNS on a solid microporous support by combining a mild hydrothermal process with chemical reduction. By using a natural sponge as a solid three-dimensional matrix for nanoparticle growth, we have synthesized highly monodisperse spherical nanoparticles with a wide size range (10-1000 nm) and extremely high yield in a relatively short period of time (1 h). Additionally, the synthesized SeNS can be stored and retrieved whenever needed by simply washing the sponge in water. Keeping the nanospheres in the support offers remarkable long-term stability as particles left on the sponge preserve their morphological and colloidal characteristics even after eight months of storage. Furthermore, this work reveals that SeNS can be used for efficient mercury capture from contaminated waters with a record-breaking mercury removal capacity of 1900 mg g.

A Nanoselenium Sponge for Instantaneous Mercury Removal to Undetectable Levels

“…[13a,15] This process results in anisotropic aggregates of nanoselenium that have a reduced surface‐to‐volume ratio as compared to single nanoparticles, poor surface coverage, and an increased risk of leaching under acidic conditions due to weak adsorption, which could represent a secondary source of pollution. This work builds on these reports and on our recent results related to the synthesis of colloidal selenium nanomaterials …”

Durable nanocomposite face masks with high particulate filtration and rapid inactivation of coronaviruses

“…The solution is impregnated into a support material followed by heating so as to begin nucleation and growth of nanoparticles within the support. Previous work has shown the efficacy of this method on polyurethane foam for environmental remediation, as well as natural and synthetic fibers for functional textiles 23 – 25 . In these materials, growth occurs within and on the surface of the substrate, and the nanoparticles become embedded in it, resulting in a nanocomposite material with improved durability and stability over traditional surface-treated products, which will leach nanoparticles over time and lose efficacy.…”

Colloidal Nanospheres of Amorphous Selenium: Facile Synthesis, Size Control, and Optical Properties

“…demonstrated a synthetic route to the preparation of ɑ‐ Se nanospheres with sizes ranging from 20 nm to sub‐micrometer [20] . Other methods have also been reported for the preparation of ɑ‐ Se nanoparticles, including those involving hydroquinone, [21] L‐cysteine, [22] ascorbic acid [23] or polysaccharides [24] as a reducing agent in an aqueous system.…”