Visible‐Light‐Active Electrospun Membranes Based on Cobalt‐Doped ZnO Nanohybrids: Applications for Food Packaging

Abstract

AbstractA cellulose acetate electrospun membrane based on Cobalt doped ZnO (Co‐ZnO) was developed. The synthesis of pure zinc oxide nanoparticles (NPs) and cobalt‐zinc oxide nanorods with varying cobalt‐to‐zinc atomic ratios of 5 %, 10 %, 15 %, and 20 % was carried out, using the co‐precipitation method. The successful incorporation of cobalt into ZnO was confirmed by using the techniques of Powder X‐ray Diffraction (PXRD), X‐ray Photoelectron Spectroscopy (XPS), and Energy Dispersive X‐ray Spectroscopy (EDX). Scanning Electron Microscopy (SEM) studies denoted the change in shape from spherical to rod‐shaped upon doping Co. A red shift was observed in band gap energies from 3.26‐3.01 eV upon increasing the Co concentration. The photocatalytic activity was evaluated, using methylene blue under sunlight and a 50 W LED lamp. The most effective photocatalyst observed in this study was a composition consisting of 15 % Co‐ZnO. When exposed to sunshine, this photocatalyst demonstrated a degradation rate of 40 % over a one‐hour period. Similarly, when subjected to a lamp, the degradation rate was found to be 24 % over the same duration. A nanofiber membrane was produced by incorporating Co‐ZnO at a concentration of 15 % (w/w) into the cellulose acetate (CA) polymer matrix by the electrospinning technique. The created CA nanofiber mat with Co‐ZnO was employed to extend the shelf life of strawberries up to 18 days along with the reduced pH increase and lower reduction of weight, firmness, and titratable acidity.