Self-Cleaning Properties of Electrospun PVA/TiO₂ and PVA/ZnO Nanofibers Composites.

Muhammad Khan,Muhammad Waqas,Abdul Abbasi,Davood Kharaghani,Sana Ullah,Yusuke Saito,Ick Kim,Chunhong Zhu

doi:10.3390/nano8090644

Abstract

In this report, polyvinyl alcohol/zinoxide (PVA/ZnO) & polyvinyl alcohol/titanium dioxide (PVA/TiO2) nanofibers were manufactured in three different concentrations of ZnO and TiO2 NPs for the application of self-cleaning properties because metallic oxides, specifically ZnO & TiO2, have the properties to remove the contaminants by hydroxyl radical (OH−1), which degrades the contaminants into small molecules and finally into CO2 and H2O. Therefore, these composites were manufactured by electrospinning. The resultant nanofibers were characterized for morphology by scan electron microscopy (SEM) & transmission electron microscopy (TEM), chemical interactions by Fourier-transform infrared (FT-IR) spectra, crystalline structure by X-ray diffraction (XRD) spectra water absorbency was evaluated by water contact angle, self-cleaning by solar simulator, and thermal degradation was done by thermogravimetric analysis (TGA) for the sake of nanoparticles the content. On the base of the characterization results it was concluded that these PVA/ZnO & PVA/TiO2 nanofibers have self cleaning properties, but PVA/ZnO nanofibers have higher self-cleaning properties than PVA/TiO2 nanofibers because PVA/ZnO nanofibers have 95% self-cleaning properties, which is higher than PVA/TiO2 nanofibers.

Highlights

In recent times nanofibres have been researched and studied widely because of their unique properties and applications [1]. Their high surface areas to volume ratio, large length to diameter ratio, and light weightiness have made them suitable for a number of applications [2]. They are widely used for filtration, drug delivery [3], tissue engineering, and sensors application in protective clothing for protection against biological and chemical hazards, food processing, and in microelectronics [4,5]
In the case of hydrophobic surfaces, water takes away the dust particles and containments that are on the material surface, which has no adhesion because of a reduced wet ability known as the lotus leaf effect [8,9]
While in case of hydrophilic surfaces developed by coating with semiconducting metal oxides dust, grease and organic containments decompose on exposure to light and are taken away by water or rain [10,11,12]

Summary

Introduction

In recent times nanofibres have been researched and studied widely because of their unique properties and applications [1] Their high surface areas to volume ratio, large length to diameter ratio, and light weightiness have made them suitable for a number of applications [2]. When a photo-catalytic surface is exposed to light of suitable energy it causes the transition of the electrons from the valence band to the conduction band, leaving behind a hole that can react with water to produce hydroxyl radical Both the hole and hydroxyl radical have very high oxidative power and can destroy organic matters and air pollutants [11]. If two exciting photo-catalysts, TiO2 and ZnO, are embedded in a suitable polymer solution, the resultant composite can effectively be used in a number of applications to destroy organic pollutants. For the sake of chemical investigation, scanning electron microscope (SEM) was done to investigate the surface morphology, transmission electron microscope (TEM) was done to investigate the dispersion of nanoparticles, and photo-catalytic activity was done to check the self-cleaning properties of the nanofibers

Materials

Method