Abstract
This paper reports the development and characterization of a multifunctional coating that combines anticorrosion and photocatalytic properties, deposited by means of the electrospinning technique. In the first step, a functional electrospun fiber mat composed of poly(acrylic acid) (PAA) and β-cyclodextrin (β-CD) was obtained, showing high water insolubility and great adhesion increased by means of a thermal crosslinking process (denoted as PAA + β-CD). In the second step, the fibers were doped with particles of titanium dioxide (denoted as PAA + β-CD/TiO2) and titanium dioxide plus iron oxide (denoted as PAA + β-CD/TiO2/Fe2O3). The morphology and fiber diameter of the electrospun mats were evaluated by using confocal microscopy, whereas the presence of the metal oxides in the electrospun fibers was corroborated by scanning electron microscopy (SEM) and X-ray fluorescence (XRF), respectively. In addition, electrochemical tests in saline solution revealed that the sample composed of PAA + β-CD/TiO2/Fe2O3 showed the highest corrosion protection efficiency of all the samples, which was directly associated to lower corrosion current density and higher corrosion potential. Furthermore, the paper reports a novel approach to in situ determination of methylene blue (MB) degradation onto the coating. The results revealed complete degradation of MB, which is perfectly appreciated by total discoloration of the film in the irradiated zone (from bluish to a white spot). The main conclusions of this research are the efficiency of the electrospun system PAA + β-CD/TiO2/Fe2O3 for developing photocatalytic activity and corrosion protection and the utility of the dry MB discoloration tests to evaluate photocatalytic activity.
Highlights
Nowadays, the implementation of surface engineering techniques with a high specific surface area is a challenging topic in the nanotechnology field thanks to the possibility of designing functionalized surfaces with advanced properties in a wide variety of industrial applications [1,2]
We presented a new onestep electrospinning process based on the synergetic effect of combining iron oxide (Fe2O3) and titanium dioxide (TiO2) into an insoluble polymeric electrospun supporting matrix
Once the electrospun coatings were fabricated as a function of the input parameters of flow rate, applied voltage, tip–collector distance and deposition time, the samples were immersed in a methylene blue solution (10 mg/L) for 24 h with the aim of obtaining a clearly bluish coating that is clearly indicative that methylene blue (MB) has been successfully incorporated into the electrospun poly(acrylic acid) (PAA) fibers
Summary
The implementation of surface engineering techniques with a high specific surface area is a challenging topic in the nanotechnology field thanks to the possibility of designing functionalized surfaces with advanced properties in a wide variety of industrial applications [1,2]. Good control in the electrospun fiber morphology can be modulated as a function of the operational parameters (flow rate, applied voltage or tip to collector distance) [20] as well as the resultant intrinsic polymeric precursor properties (concentration, viscosity, surface tension, conductivity, nature of solvent) [21] Another important aspect is that the electrospinning technique can be implemented for precursors of different nature, such as water soluble, water insoluble or even biocompatible polymers. The experimental results have demonstrated simultaneous enhancement in photocatalytic performance under both UV and visible light, which was corroborated by the degradation of a dye pollutant (methylene blue, MB), as well as in the resultant corrosion resistance These findings, associated to this specific surface area morphology, can be used as an efficient eco-friendly and economical alternative for its implementation on a real industrial scale.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
