Emerald eco-synthesis: harnessing oleander for green silver nanoparticle production and advancing photocatalytic MB degradation with TiO2&CuO nanocomposite.

The tertiary composite of TiO2/CuO @ Ag (TCA) were synthesized by the solid state method using different ratios of TiO2/CuO NCs and Ag NPs. The structural, morphological, and optical properties of nanocomposites were analyzed by scanning electron microscope, Transmission electron microscope, X-ray diffraction, Fourier transform infrared spectra, UV-Vis diffuse reflectance spectra (UV-Vis/DRS) and photoluminescence spectrophotometry. The results showed enhanced activity of TCA hybrid nano crystals in oxidizing MB in water under visible light irradiation compared to pure TiO2. The photocatalytic performance TCA samples increased with suitable Ag content. The results show that the photo degradation efficiency of the TiO2 compound improved from 13 to 85% in the presence of TiO2-CuO and to 98.87% in the presence of Ag containing TiO2-CuO, which is 7.6 times higher than that of TiO2. Optical characterization results show enhanced nanocomposite absorption in the visible region with long lifetimes between e/h+ at optimal TiO2-CuO/Ag (TCA2) ratio. Reusable experiments indicated that the prepared TCA NC photo catalysts were stable during MB photo degradation and had practical applications for environmental remediation.

Efficient photocatalytic degradation of organic pollutants over TiO2 nanoparticles modified with nitrogen and MoS2 under visible light irradiation.

Investigate the use of visible light to improve photocatalytic degradation of organic pollutants in wastewater. Nitrogen-doped titania and molybdenum sulfide nanocomposites (NTM NCs) with different weight ratios of MoS2 (1, 2, and 3 wt.%) synthesized by a solid state method applied to the photodegradation of methylene blue(MB) under visible light irradiation. The synthesized NTM composites were characterized by SEM, TEM, XRD, FT-IR, UV-Vis, DRS and PL spectroscopy. The results showed enhanced activity of NTM hybrid nanocrystals in oxidizing MB in water under visible light irradiation compared to pure TiO2. The photocatalytic performance of NTM samples increased with MoS2 content. The results show that the photodegradation efficiency of the TiO2 compound improved from 13 to 82% in the presence of N-TiO2 and to 99% in the presence of MoS2 containing N-TiO2, which is 7.61 times higher than that of TiO2. Optical characterization results show enhanced nanocomposite absorption in the visible region with long lifetimes between e/h+ at optimal N-TiO2/MoS2 (NTM2) ratio. Reusable experiments indicated that the prepared NTM NCs photocatalysts were stable during MB photodegradation and had practical applications for environmental remediation.

Hybrid magnetic core-shell TiO2@CoFe3O4 composite towards visible light-driven photodegradation of Methylene blue dye and the heavy metal adsorption: isotherm and kinetic study.

Magnetic core-shell TiO2@CoFe3O4 (TCM) composite photocatalytic particles with a core-shell structure were synthesized by the co-precipitation method as a novel catalyst for methylene blue (MB) dye degradation and adsorption efficiency of heavy-metal ion Pb(II) from aqueous solution. Various analytical techniques have verified the formation of the TCM core-shell through TEM, XRD, FT-IR, Raman, PL, and UV analysis. The presence of TiO2 and cobalt magnetite in the TCM core shell is confirmed by XRD analysis. The formation of a homogenous CoFe3O4shell on TiO2 spheres is confirmed by HR-TEM investigation. TiO2 nanoparticle has a rutile structure with an average crystallite size of about 57.44 and a TCM core-shell of about 64.62 nm. From UV and PL studies, it was found that the core shell absorbs the visible range of the electromagnetic spectrum, which improves the effective separation between photo carriers. This study focused on several factors that influence metal ion adsorption, including initial concentrations, adsorbent dose, pH, and contact time. The TCM nanocomposite successfully separated the heavy metal ion Pb(II) from aqueous solutions, and the model predictions exactly matched the experimental results. For TCM material, the maximum adsorption efficiency for Pb(II) was 33.09 mg/g. The photocatalytic performance of TiO2 and TCM is about 12% and 91% after 60 min for MB dye degradation. It was found that TiO2@CoFe3O4 core-shell nanoparticles perform better as photo catalysts than pure TiO2 and CoFe3O4due to their high efficiency and reusability. Furthermore, the analysis revealed that heavy metal adsorption from aqueous solutions could be reused over seven cycles with no adsorption capacity modification.

Magnetic ZnO Crystal Nanoparticle Growth on Reduced Graphene Oxide for Enhanced Photocatalytic Performance under Visible Light Irradiation.

Magnetite zinc oxide (MZ) (Fe3O4/ZnO) with different ratios of reduced graphene oxide (rGO) was synthesized using the solid-state method. The structural and optical properties of the nanocomposites were analyzed using transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis/DRS), and photoluminescence (PL) spectrophotometry. In particular, the analyses show higher photocatalytic movement for crystalline nanocomposite (MZG) than MZ and ZnO nanoparticles. The photocatalytic degradation of methylene blue (MB) with crystalline ZnO for 1.5 h under visible light was 12%. By contrast, the photocatalytic activity for MZG was more than 98.5%. The superior photocatalytic activity of the crystalline nanocomposite was detected to be due to the synergistic effect between magnetite and zinc oxide in the presence of reduced graphene oxide. Moreover, the fabricated nanocomposite had high electron-hole stability. The crystalline nanocomposite was stable when the material was used several times.