Preparation and characterization of polyphosphotungstate/ZrO2 nanocomposite and their sonocatalytic and photocatalytic activity under UV light illumination

Abstract

Polyoxometalates (POM) supported on zirconia, H(3)PW(12)O(40)/ZrO2, were prepared by incorporating polyphosphotungstate into a zirconia matrix via sol-gel technique that involving the hydrolysis of zirconium (IV) n-butoxide, Zr (n-OBu)(4), as the ZrO(2) source. This insoluble and readily separable catalyst was characterized by using XRD, FT-IR, SEM, and UV diffuse reflectance spectroscopy (UV-DRS), indicating that the polyphosphotungstate was chemically attached to the zirconia supports, and primary Keggin structure remained intact. The photocatalytic and sonocatalytic activity of the supported polyphosphotungstate was tested via degradation of different dyes in aqueous solutions. The POM-ZrO(2) nanocomposite showed higher photocatalytic and sonocatalytic activity than pure polyoxometalate or pure ZrO(2).

Improving the sonocatalytic performance of good crystallinity ZrO2 nanocomposite through graphene addition

“…The sonocatalytic mechanism of pure ZrO2 has been studied previously [14]. In the presence of graphene, the rate of the recombination electron-hole pairs might be inhibited due to the trapping of electrons by graphene layers.…”

Ultrasonic-assisted degradation of phenazopyridine with a combination of Sm-doped ZnO nanoparticles and inorganic oxidants

“…As a result, more generated holes can transfer to the surface of ZnO nanoparticles and oxidize the adsorbed H 2 O molecules or OH À ions to produce Å OH radicals (Eqs. (9) and (10)) that are responsible for degradation of organic compounds [33,34].…”

“…On the other hand, ultrasonic irradiation can bring about the formation of intense ultraviolet light with a relatively extensive variety of wavelengths (below 375 nm), named sonoluminescence, which can to excite the semiconductors to act as a photocatalyst during ultrasonic irradiation [9][10][11].…”

Fabrication of meso-porous BiOI sensitized zirconia nanoparticles with enhanced photocatalytic activity under simulated solar light irradiation

“…The recent research is focused on the fabrication of new and alternative visible light active nano-materials to traditional TiO 2 . Zirconium oxide (ZrO 2 ) is also an environmentally friendly semiconductor metal oxide with high refractive index and good photocatalytic property [14][15][16] when compared to TiO 2 . The wide band gap, low quantum yield and high recombination of photo-generated electron-hole pairs hamper the practical application of ZrO 2 under visible light (nearly 45% of solar light).…”