Ultrasonic-assisted preparation of ZrO2/g-C3N4 nanocomposites with high visible-light photocatalytic activity for degradation of 4-chlorophenol in water

Abstract

Various methods including photocatalysis have been used for degradation and removal of phenolic compounds, which classified as hazardous materials in the environment. Nanomaterials exhibited significant advantages for photocatalytic degradation of phenolic compounds compared to the conventional oxidation approaches such as traditional biological and physical methods. In this study, zirconia (ZrO2)/graphitic carbon nitride (g-C3N4) nanocomposites were successfully synthesized using ultrasonication method and used for photodegradation of 4-chlorophenol (4-CP) in water under visible light. The g-C3N4 nanosheets, ZrO2 nanoparticles (NPs), and ZrO2/g-C3N4 nanocomposite were characterized by N2 adsorption, X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy (DRS), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM), photoelectrochemical (PEC) measurements, and photoluminescence spectroscopy (PL). The incorporation of ZrO2 NPs enhanced the surface area and light absorption capacity of pristine g-C3N4. The photocatalytic activity of ZrO2/g-C3N4 nanocomposite sample was evaluated by the degradation of 4-CP in aqueous medium. Results exhibited an increase in photocatalytic activity of ZrO2/g-C3N4 nanocomposite compared to unmodified ZrO2 NPs and pristine g-C3N4. In addition, reusability experiment of ZrO2/g-C3N4 nanocomposite for photo-catalytic degradation, as well as for 4-CP adsorption showed the ZrO2/g-C3N4 nanocomposites can be effectively used for several cycles.