Piezo-Enhanced Photocatalytic Activity of the Electrospun Fibrous Magnetic PVDF/BiFeO3 Membrane

Abstract

Creating stimulus-sensitive smart catalysts capable of decomposing organic dyes with high efficiency is a critical task in ecology. Combining the advantages of photoactive piezoelectric nanomaterials and ferroelectric polymers can effectively solve this problem by collecting mechanical vibrations and light energy. Using the electrospinning method, we synthesized hybrid polymer-inorganic nanocomposite fiber membranes based on polyvinylidene fluoride (PVDF) and bismuth ferrite (BFO). The samples were studied by scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), total transmittance and diffuse reflectance, X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), vibrating-sample magnetometer (VSM), and piezopotential measurements. It has been demonstrated that the addition of BFO leads to an increase in the proportion of the polar phase from 86.5% to 96.1% due to the surface ion–dipole interaction. It is shown that the composite exhibits anisotropy of magnetic properties depending on the orientation of the magnetic field. The results of piezo-photocatalytic experiments showed that under the combined action of ultrasonic treatment and irradiation with both visible and UV light, the reaction rate increased in comparison with photolysis, sonolysis, and piezocatalysis. Moreover, for PVDF/BFO, which does not exhibit photocatalytic activity, under the combined action of light and ultrasound, the reaction rate increases by about 3× under UV irradiation and by about 6× under visible light irradiation. This behavior is explained by the piezoelectric potential and the narrowing of the band gap of the composite due to mechanical stress caused by the ultrasound.

1D/2D Electrospun Polyvinylidene Fluoride Nanofibers/Carbon Flakes Hybrid Nonmetal Polymeric Photo‐ and Piezocatalyst

“…According to the works, [41–42] the most appropriate method for quantitative analysis of phase distribution in PVDF‐based samples is Fourier transform infrared (FTIR) spectroscopy. FTIR spectra were obtained for all the samples investigated, and the data are presented in Figure 4.…”

“…The reaction rate for PVDF/C 0.5 is 2.7 times higher than that of PVDF/C 1.5 and 10.3 times higher than that of pure PVDF. The very low photocatalytic activity of PVDF (lower than photolysis) is attributed to the giant light scattering characteristics of PVDF fibers [43] and its low absorption coefficient [41] …”

“…Smaller particles distributed along the fibers can act as nucleating agents and accelerate the crystallization rate, thereby promoting the formation of a polar β-phase. [40] According to the works, [41][42] the most appropriate method for quantitative analysis of phase distribution in PVDF-based samples is Fourier transform infrared (FTIR) spectroscopy. FTIR spectra were obtained for all the samples investigated, and the data are presented in Figure 4.…”

Electrochemical Synthesis of Superparamagnetic Fe3O4 Nanoparticles for the Photo‐Fenton oxidation of Rhodamine B

“…[5,6] To avoid the negative impact on the environment and human health, the treatment of dyes wastewater should be carried out using environmentally friendly technologies, such as adsorption, membrane filtration etc. [7][8][9][10][11][12] The most promising technologies for cleaning dyes contaminated wastewater are advanced oxidation processes (AOPs), which can effectively remove organic compounds. [13][14][15][16][17] The advantage of AOPs over other treatment methods is that they are "environmentally friendly" because they do not transfer pollutants from one phase to another (e. g., coagulation and adsorption) and do not generate large amounts of hazardous sludge as in the case of biological treatment.…”

“…The presence of dyes in the environment has serious negative consequences for nature and human health, as dyes can be toxic to aquatic organisms that are part of the food chain [5,6] . To avoid the negative impact on the environment and human health, the treatment of dyes wastewater should be carried out using environmentally friendly technologies, such as adsorption, membrane filtration etc [7–12] . The most promising technologies for cleaning dyes contaminated wastewater are advanced oxidation processes (AOPs), which can effectively remove organic compounds [13–17] .…”