Photocatalytic degradation of phenolic pollutants over palladium-tungsten trioxide nanocomposite

In this work, we successfully developed palladium nanoparticles anchored on nitrogen, sulfur-doped tungsten trioxide (Pd@NSC-WO3) by microwave-solvothermal (MW-ST) technique. Herein, we report Pd@NSC-WO3 as a multifunctional photocatalyst for phenolic pollutants (PPs) including hydroquinone (HQ), resorcinol (RC), and catechol (CC). The synthesized photocatalysts were characterized using X-ray diffraction (XRD), BrunauerEmmett-Teller (BET) surface area analysis, hydrogen temperature programmed reduction (H-2-TPR), Fourier transform infra-red (FT-IR), field emission scanning electron microscopy (FE-SEM), field emission transmission electron microscopy (FE-TEM), selected area electron diffraction (SAED), energy dispersive X-ray analysis (EDS), ultraviolet-visible spectroscopy (UV-vis), X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) techniques. It exhibits an enhanced photocatalytic degradation efficiency were archived under both UV and visible light (VL). The interaction between Pd and WO3 and the presence of heteroatoms like N and S, which promote the photodegradation of PPs in the direct pathway and provided excellent stability. The formed intermediate products during PPs photodegradation were identified by liquid chromatography-mass spectrometry (LC-MS) technique. The trapping experiments confirmed that center dot OH and center dot O-2(-) were active radicals during the degradation process. More importantly, after being tested in five cycles, Pd@NSC-WO3 showed a good photocatalytic performance due to its chemical stability. In practice, the excellent properties associated with the novel Pd@NSC-WO3 indicated that they could be considered as a promising light-driven photocatalyst to remove the PPs contamination in water.