Development of Efficient Antimicrobial Zinc Oxide Modified Montmorillonite Incorporated Polyacrylonitrile Nanofibers for Particulate Matter Filtration

Abstract

Ultrafine particulate matter and airborne microorganisms present in atmosphere are responsible for affecting the human health and the global climate. The development of bifunctional membranes which can simultaneously filter the particulate matter (PM) and inhibit the growth of microorganisms is the need of the hour. In this study, electrospun polyacrylonitrile (PAN)/zinc oxide modified montmorillonite (ZnO-Mt) nanofibrous nanocomposites with varying concentrations of ZnO-Mt ranging from 0.25 % to 1.00 % (w/w) have been prepared to be used as filtration membranes. The addition of ZnO-Mt in PAN dope solution affects its viscosity and ionic conductivity. The surface morphology of the nanofibrous membranes was studied using field emission scanning electron microscopy. The average diameter of PAN nanofibers and its nanocomposites was found to be between 247 nm to 468 nm. An increase in porosity, air permeability and water vapor transmission rate of the nanofibrous membranes was observed with an increase in concentration of ZnO-Mt in PAN nanofibers upto 0.75 %. The addition of ZnO-Mt enhanced the thermal stability of PAN nanofibrous membranes from 188 °C to 310 °C. The filtration efficiency of the nanofibrous membranes was evaluated using environment particle air monitor instrument. PAN/ZnO-Mt nanofibrous membranes having 0.75 % w/w ZnO-Mt exhibited filtration efficiency of 99.6 %. The antimicrobial property of PAN/ZnO-Mt nanofibrous membranes was studied against S. aureus and E. coli bacterial strains showing 98.85 % and 96.23 % antibacterial activity respectively.