Sponge-supported synthesis of colloidal selenium nanospheres

Biomimetic mercury immobilization by selenium functionalized polyphenylene sulfide fabric

Highly efficient decontamination of elemental mercury (Hg0) remains an enormous challenge for public health and ecosystem protection. The artificial conversion of Hg0 into mercury chalcogenides could achieve Hg0 detoxification and close the global mercury cycle. Herein, taking inspiration from the bio-detoxification of mercury, in which selenium preferentially converts mercury from sulfoproteins to HgSe, we propose a biomimetic approach to enhance the conversion of Hg0 into mercury chalcogenides. In this proof-of-concept design, we use sulfur-rich polyphenylene sulfide (PPS) as the Hg0 transporter. The relatively stable, sulfur-linked aromatic rings result in weak adsorption of Hg0 on the PPS rather than the formation of metastable HgS. The weakly adsorbed mercury subsequently migrates to the adjacent selenium sites for permanent immobilization. The sulfur-selenium pair affords an unprecedented Hg0 adsorption capacity and uptake rate of 1621.9 mg g-1 and 1005.6 μg g-1 min-1, respectively, which are the highest recorded values among various benchmark materials. This work presents an intriguing concept for preparing Hg0 adsorbents and could pave the way for the biomimetic remediation of diverse pollutants.

Highly efficient and durable antimicrobial nanocomposite textiles

Healthcare associated infections cause millions of hospitalizations and cost billions of dollars every year. A potential solution to address this problem is to develop antimicrobial textile for healthcare fabrics (hospital bedding, gowns, lab coats, etc.). Metal nanoparticle-coated textile has been proven to possess antimicrobial properties but have not been adopted by healthcare facilities due to risks of leaching and subsequent loss of function, toxicity, and environmental pollution. This work presents the development and testing of antimicrobial zinc nanocomposite textiles, fabricated using a novel Crescoating process. In this process, zinc nanoparticles are grown in situ within the bulk of different natural and synthetic fabrics to form safe and durable nanocomposites. The zinc nanocomposite textiles show unprecedented microbial reduction of 99.99% (4 log₁₀) to 99.9999% (6 log₁₀) within 24 h on the most common Gram-positive and Gram-negative bacteria, and fungal pathogens. Furthermore, the antimicrobial activity remains intact even after 100 laundry cycles, demonstrating the high longevity and durability of the textile. Independent dermatological evaluation confirmed that the novel textile is non-irritating and hypoallergenic.

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

The COVID-19 pandemic presents a unique challenge to the healthcare community due to the high infectivity rate and need for effective personal protective equipment. Zinc oxide nanoparticles have shown promising antimicrobial properties and are recognized as a safe additive in many food and cosmetic products. This work presents a novel nanocomposite synthesis approach, which allows zinc oxide nanoparticles to be grown within textile and face mask materials, including melt-blown polypropylene and nylon-cotton. The resulting nanocomposite achieves greater than 3 log10 reduction (≥ 99.9%) in coronavirus titer within a contact time of 10 min, by disintegrating the viral envelope. The new nanocomposite textile retains activity even after 100 laundry cycles and has been dermatologist tested as non-irritant and hypoallergenic. Various face mask designs were tested to improve filtration efficiency and breathability while offering antiviral protection, with Claros' design reporting higher filtration efficiency than surgical masks (> 50%) for particles ranged 200 nm to 5 µm in size.

Versatile Process for the Preparation of Nanocomposite Sorbents: Phosphorus and Arsenic Removal

Nanomaterials are being increasingly utilized for environmental remediation. The use of these materials, however, is greatly hindered due to challenges in material handling and deployment. Here we present a novel nanocomposite synthesis method based on the direct growth of nanoparticles on and within solid support materials, referred to as Crescoating. In this work, iron and copper nanoparticles have been grown on polyurethane support materials using this process and applied as sorbents for dissolved phosphorus and arsenic in water, respectively. These nanocomposite sorbents exhibit rapid sorption with saturation occurring in less than 5 min. The loading capacity is 104.8 mg PO₄^3- g^-1 and 254.4 mg As(III) g^-1 for the iron and copper nanocomposite sorbents respectively, which is up to four times higher than commercially available alternatives. In addition, phosphorus can be recovered from the iron nanocomposite sorbent. This coating by growth process produces nanocomposites that do not emit particles and has the capability to be scaled and applied to other nanoparticles for diverse pollutant sorption applications.

Selenium nanoparticle prepared by femtosecond laser-induced plasma shock wave

A novel approach for the production of both amorphous and crystalline selenium nanoparticles (SeNPs) using femtosecond laser-induced plasma shock wave on the surface of Bi₂Se₃ topological insulators at room temperature and ambient pressure is demonstrated. The shape and size of SeNPs can be reliably controlled via the kinetic energy obtained from laser pulses, so these are applicable as active components in nanoscale applications. Importantly, the rapid, low-cost and eco-friendly synthesis strategy developed in this study could also be extendable to other systems.