Practical implementation of large-scale treatment systems based on natural materials. MN-C/Fs are effective for treating industrial effluents and reprocessing spent materials sustainably.

Pure and modified mesoporous TiO₂ nanoparticles with different loadings of NiO (3–20.0 wt %) were prepared through the surfactant-assisted sol–gel approach with the use of cetyltrimethylammonium bromide as a template. The optical and structural properties of different samples were examined using N₂ adsorption–desorption analysis, energy-dispersive spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV–vis spectroscopy, Fourier transform infrared spectroscopy, and photoluminescence (PL) spectroscopy. X-ray diffraction results confirmed the insertion of Ni²⁺ into the lattice of TiO₂, and the crystallite size reduced remarkably after the addition of NiO. The diffuse reflectance spectroscopy spectra displayed obvious red shift in the absorption edges, and new absorption bands appeared in the visible region when NiO was added, which indicates the formation of surface defects and oxygen vacancies. The optical band gap of TiO₂ reduced sharply when the contents of NiO were increased. The increase in the surface defects as well as oxygen vacancies were examined using PL spectroscopy. The photocatalytic performance of the as-synthesized samples was investigated over photodegradation of brilliant green (BG) and phenol and hydrogen generation under visible light. 10% NiO/TiO₂ exhibited the highest photocatalytic efficiency. The photocatalytic activity was improved due to the creation of a p–n junction at the interface of NiO/TiO₂, which efficiently promotes the separation of photogenerated electron/hole pairs and consequently enhances its photodegradation activity. According to the photocatalytic activity results, NiO contents were considered one of the most important factors affecting the photodegradation of BG and phenol and H₂ evolution. Also, we discussed the mechanism of photodegradation, mineralization (total organic carbon), and photocatalytic reaction kinetics of BG and phenol.

Pd nanoparticles were loaded on Co x –Mn _(1−x) -MOF-74. 5 wt% Pd@Co _0.5 –Mn _0.5 -MOF-74 was the most effective catalyst for CO oxidation. The prepared catalysts displayed excellent stability during CO oxidation without significant decrease in catalytic performance.

Recently, efficient decontamination of water and wastewater have attracted global attention due to the deficiency in the world’s water sources. Herein, activated carbon (AC) derived from willow catkins (WCs) was successfully synthesized using chemical modification techniques and then loaded with different weight percentages of nickel ferrite nanocomposites (10, 25, 45, and 65 wt.%) via a one-step hydrothermal method. The morphology, chemical structure, and surface composition of the nickel ferrite supported on AC (NFAC) were analyzed by XRD, TEM, SEM, EDX, and FTIR spectroscopy. Textural properties (surface area) of the nanocomposites (NC) were investigated by using Brunauer–Emmett–Teller (BET) analysis. The prepared nanocomposites were tested on different dyes to form a system for water remediation and make this photocatalyst convenient to recycle. The photodegradation of rhodamine B dye was investigated by adjusting a variety of factors such as the amount of nickel in nanocomposites, the weight of photocatalyst, reaction time, and photocatalyst reusability. The 45NFAC photocatalyst exhibits excellent degradation efficiency toward rhodamine B dye, reaching 99.7% in 90 min under a simulated source of sunlight. To summarize, NFAC nanocomposites are potential photocatalysts for water environmental remediation because they are effective, reliable, and reusable.