Solution blow spun silica nanofibers: Influence of polymeric additives on the physical properties and dye adsorption capacity

Authors: DE COSTA FARIAS, ROSIANE MARIA - Federal University Of Campina Grande; LEITE SEVERO, LUCAS - Federal University Of Campina Grande; Klamczynski, Artur; DE MEDEIROS, ELITON SOUTO - Universidade Federal Da Paraiba (UFPB); DE LIMA SANTANA, LISIANE NAVARRO - Federal University Of Campina Grande; DE ARAUJO NEVES, GELMIRES - Federal University Of Campina Grande; Glenn, Gregory - Greg; MENEZES, R - Federal University Of Campina Grande

Submitted to: Nanomaterials
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/9/2021
Publication Date: 11/20/2021
Citation: De Costa Farias, R., Leite Severo, L., Klamczynski, A.P., de Medeiros, E., de Lima Santana, L., de Araujo Neves, G., Glenn, G.M., Menezes, R. 2021. Solution blow spun silica nanofibers: Influence of polymeric additives on the physical properties and dye adsorption capacity. Nanomaterials. 11(11). Article 3135. https://doi.org/10.3390/nano11113135.
DOI: https://doi.org/10.3390/nano11113135

Interpretive Summary: TITLE: Silica nanofibers that are effective adsorbents. Various chemicals and heavy metals may be present as contaminants in water and need to be efficiently removed to make the water more safe for use. ARS scientists collaborated with Brazilian scientists to investigate the use of polymers with different molecular weights in producing silica nanofibers with different pore sizes. Silica nanofibers with a high percentage of pores in the mesopore size range were effective in adsorbing dye molecules that are considered a contaminant in dye processes. The results show that pore sizes can be controlled in making silica nanofiber filtration materials that selectively adsorb contaminants from water.

Technical Abstract: The textural properties of porous silica nanofibers are an important factor that impacts their performance in various applications. Most pore structures are formed using surfactants as a template added to a polymer precursor solution. However, no effort has been given to study the effect of the polymer on the physical properties of the nanofibers produced by the solution blow spinning (SBS) technique. In this study, porous silica nanofibers were produced via SBS from a silica precursor/polymer solution. Polyvinylpyrrolidone (PVP, Mw = 360,000 and 1,300,000) samples were chosen as spinning aids and to create different pore properties. In addition, the effect of their physical properties on the adsorption of methylene blue (MB) in aqueous solution was explored. After forming fibers by the SBS process, the nanofibers were calcined to remove the organic polymer phase and create porous, silica-rich nanofibers. The calcined nanofibers had a large amount of micro and mesopores without the use of additional surfactants. The molecular weight of the PVP chains impacted the growth of silica particles and consequently the pore size. High molecular weight PVP inhibited the growth of silica particles, resulting in a large volume of micropores. On the other hand, silica nanofibers with a high fraction of mesopores were obtained using the lower molecular weight PVP. In the adsorption process, the presence of easily accessible mesopores in silica nanofibers improved the adsorption performance of large MB molecules. These results demonstrate a simple method of producing blow spun silica nanofibers with defined variations of pore sizes by varying only the molecular weight of the polymer. These results demonstrate an efficient method for making adsorbents that can selectively adsorb specific target molecules.