Activity For Degradation Of 4-nitrophenol Research Articles

Synthesis of Fe3O4/CdWO4/carbon dots heterostructure with excellent visible light photocatalytic stability and activity for degradation of 4-nitrophenol and organic pollutant

Synthesis of Fe3O4/CdWO4/carbon dots heterostructure with excellent visible light photocatalytic stability and activity for degradation of 4-nitrophenol and organic pollutant

Impact of CuO doping on the properties of CdO thin films on the catalytic degradation by using pulsed-Laser deposition technique

This study is an attempt to present a novel idea for enhancing the properties of the CdO thin film onto the quartz substrate by doping CuO on the catalytic activity for degradation of 4-nitrophenol. In this work, the CuO doped CdO thin film is carried by switching of targets between Cd and Cu by Pulsed Laser Deposition (PLD) Technique via nanosecond Nd:YAG laser to enhance the performance of the as-prepared CdO thin film, which are performed by various spectroscopic techniques. From X-ray diffraction, the crystallinity of CdO thin film was improved in the case of doping with CuO due to the grain growth by increasing the intensity of the diffraction peaks at (111) and decreasing the intensity of the diffraction peaks at (200) with slightly shifted toward higher value. From UV–visible spectroscopy, the maximum value of transmittance in the visible region of CdO was decreased after doping with CuO due to a less scattering property and high structural homogeneity. From photoluminescence, the emission intensity decreases related to the presence of impurities of CuO ions. From Fourier transform infrared spectroscopy, the stretching vibration modes are based on CdO and CuO structure. The scanning electron microscope showed a semi-spherical shape of CdO structure with some irregular shape nanoparticles related to CuO structure. After that, the catalytic activity for degradation of 4-nitrophenol of the CdO thin film is improved after doping with CuO from 0% to 92.3% within 2 h.

TiO 2 nanoparticles incorporated with CuInS 2 clusters: preparation and photocatalytic activity for degradation of 4-nitrophenol

TiO 2 nanoparticles incorporated with CuInS 2 clusters were prepared in a solvothermal process and characterized with X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy-dispersion X-ray analysis (EDX). Compared with pure TiO 2 nanoparticles, the TiO 2 nanoparticles incorporated with CuInS 2 clusters display higher photocatalytic activity with 99.9% of degradation ratio of 4-nitrophenol after 2 h irradiation. In order to investigate the effect of the CuInS 2 clusters on the photocatalytic activity of TiO 2 nanoparticles, diffuse reflectance UV–Vis spectra (DRS), photoluminescence (PL) spectra, and photocurrent action spectra were measured. The results indicate that the enhanced photocatalytic activity is probably due to the interface between TiO 2 and CuInS 2 as a trap of the photogenerated electrons to decrease the recombination of electrons and holes.

Physico-chemical characterisation and photocatalytic activity of nanosized SO42−/TiO2 towards degradation of 4-nitrophenol

Abstract Unmodified and sulphate-modified TiO 2 samples of different crystal forms and crystal sizes were prepared at different pH, varying the source and concentration of sulphate ion and by activating at different temperatures. The samples were characterised by XRD, FT-IR, TEM and nitrogen adsorption–desorption methods. The TEM and XRD patterns revealed that TiO 2 sample prepared at lower pH (pH 3) exhibit smaller crystallite size than that of higher pH (pH 9). Sulphate ion impregnation also decreases the crystallite size and stabilises the anatase phase of TiO 2 at higher activation temperatures. FT-IR results show that sulphate species strongly bound bidentately on TiO 2 surface. Surface area is more in case of sample prepared at lower pH than that of higher pH and also found to increase with the increase in sulphate loading up to 7.5 wt.% and thereafter decreases drastically. The photocatalytic activities of the catalysts were compared by performing degradation of 4-nitrophenol as a probe reaction. Photocatalytic degradation of 4-nitrophenol depends on surface area, the crystal form and particle size of TiO 2 . Samples containing mixture of anatase and rutile phases exhibit highest activity for degradation of 4-nitrophenol than that of other samples.