Photocatalytic and Antimicrobial Properties of Electrospun TiO₂–SiO₂–Al₂O₃–ZrO₂–CaO–CeO₂ Ceramic Membranes

Abstract

In this study, TiO 2 -based ceramic nanofiber membranes in the system of TiO 2 −SiO 2 −Al 2 O 3 −ZrO 2 −CaO− CeO 2 were synthesized by combining sol−gel and electrospinning processes. In order to investigate the thermal treatment temperature effect, the obtained nanofiber membranes were calcined at different temperatures ranging from 550 to 850 °C. Different characterization methods such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), and high-resolution transmission electron microscopy (HR-TEM) were conducted on the obtained membranes to investigate the structural and morphological properties of the nanofibers. The Brunauer−Emmett−Teller surface area of the nanofiber membranes was very high (46.6−149.2 m 2 /g) and decreased with increasing calcination temperature as expected. Photocatalytic activity investigations were determined using methylene blue (MB) as a model dye under UV and sunlight irradiation. High degradation performances were achieved with the calcination temperatures of 650 and 750 °C because of the high specific surface area and the anatase structure of the nanofiber membranes. Moreover, the ceramic membranes showed antibacterial activity against Escherichia coli as a Gram-negative bacterium and Staphylococcus aureus as a Gram-positive bacterium. The superior properties of the novel TiO 2 -based multi-oxide nanofiber membranes proved as a promising candidate for various industries, especially the removal of textile dyes from wastewater.

Self-Cleaning and Charge Transport Properties of Foils Coated with Acrylic Paint Containing TiO2 Nanoparticles

“…In the construction industry, the application of TiO 2 photocatalysis has promoted several new materials [9] whose surfaces are functionalized with self-cleaning [10], depolluting [11], and antimicrobial properties [12]. Photocatalytic active aluminum films [13], ceramics [14,15], glass [16], mortars, and cement [17,18] have been synthesized using TiO 2 nanoparticles as a surface coating or embedded in the bulk [6].…”

Electrospinning Nonspinnable Sols to Ceramic Fibers and Springs

“…Although many well-established precursor solution systems exist, modifying them by introducing other ions, tuning pH, or blending with other nanomaterial additives might trigger polymer participation, cross-linking, and phase segregation, making these solutions nonspinnable . Also, a good solvent is required to dissolve a certain amount of polymer to allow sufficient polymer chain entanglement. , Yet, the ceramic precursors dispersed in such polymer/solvent medium tend to segregate into various phases due to their varied solubility, resulting in porous structures and unevenly distributed crystalline and amorphous phases. − Possible phase separations in the solution also makes creating homogeneous multicomponent and high entropy ceramic fibers very challenging. − Moreover, in the precursor fibers, the polymer intermixes with the sol–gel species and occupies a significant volume of the materials (typically about 40–60 wt %), removing the polymer leaves inorganic fibers with rough surfaces and pores. These structural defects severely deteriorate the mechanical properties of calcined ceramic fibers, , limiting their installation in applications such as filtration, biomedical engineering, sensing, automobiles, energy generation, storage, etc . − …”