Photocatalytic Activity of Ag Nanoparticles Deposited on Thermoexfoliated g-CN.

The limited access to fresh water and the increased presence of emergent pollutants (EPs) in wastewater has increased the interest in developing strategies for wastewater remediation, including photocatalysis. Graphitic carbon nitride (g-CN) is a 2D non-metal material with outstanding properties, such as a 2.7 eV bandgap and physicochemical stability, making it a promising photocatalyst.

Antimicrobial and Virus Adsorption Properties of Y-Zeolite Exchanged with Silver and Zinc Cations.

The antimicrobial activity of silver and zinc exchanged cations in Y-zeolite (Ag/CBV-600, Zn/CBV-600) is evaluated against (gram (+)) and (gram (-)) bacteria along with their adsorption capacity for viruses: brome mosaic virus (BMV), cowpea chlorotic mottle virus (CCMV), and the bacteriophage MS2. The physicochemical properties of synthesized nanomaterials are characterized by inductively coupled plasma optical emission spectroscopy (ICP-OES), UV-Vis spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). According to the obtained results, the main species associated with the exchanged ions are Ag and Zn cations with the concentration of around 1 atomic %.

Photocatalytic Activity and Biocide Properties of Ag-TiO Composites on Cotton Fabrics.

Composites of Ag and TiO nanoparticles were synthesized in situ on cotton fabrics using sonochemical and solvothermal methods achieving the successive formation of Ag-NPs and Ti-NPs directly on the fabric. The impregnated fabrics were characterized using ATR-FTIR spectroscopy; high-resolution microscopy (HREM); scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS); Raman, photoluminescence, UV-Vis, and DRS spectroscopies; and by tensile tension tests. Results showed the successful formation and impregnation of NPs on the cotton fabric, with negligible leaching of NPs after several washing cycles.

Green Thermo-Photo Catalytic Production of Syngas Using Pd/Nb-TiO Catalysts.

In this contribution, a series of Pd-promoted Nb-doped titania samples were essayed in the gas-phase thermo-photo production of syngas from methanol/water mixtures. The Pd loading was tested in the 0.1 to 2.

Mordenite-Supported Ag-Cu-Zn Trimetallic System: A Variety of Nanospecies Obtained via Thermal Reduction in Hydrogen Followed by Cooling in an Air or Hydrogen Atmosphere.

Multimetallic systems, instead of monometallic systems, have been used to develop materials with diverse supported species to improve their catalytic, antimicrobial activity, etc., properties. The changes in the types of nanospecies obtained through the thermal reduction of ternary Ag-Cu-Zn/mordenite systems in hydrogen, followed by their cooling in an air or hydrogen atmosphere, were studied.

Characterization and photocatalytic activity of TiO nanoparticles on cotton fabrics, for antibacterial masks.

The impregnation of two commercial cotton fabrics (lab coat and Indiolino) with TiO nanoparticles (TiO-NPs) was carried out. For this, two commercial cotton fabrics were dipped in titanium isopropoxide, titanium butoxide and titanium tetrachloride solutions to the TiO-NPs formation and in-situ TiO-NPs impregnation on the cotton fabric surface by the sonochemical, hydrothermal and solvothermal methods, respectively. The impregnated fabrics were characterized by ATR-FTIR, SEM-EDS, Raman, UV-Vis, DRS and tension tests.

Recent Advances in Catalysis Based on Transition Metals Supported on Zeolites.

This article reviews the current state and development of thermal catalytic processes using transition metals (TM) supported on zeolites (TM/Z), as well as the contribution of theoretical studies to understand the details of the catalytic processes. Structural features inherent to zeolites, and their corresponding properties such as ion exchange capacity, stable and very regular microporosity, the ability to create additional mesoporosity, as well as the potential chemical modification of their properties by isomorphic substitution of tetrahedral atoms in the crystal framework, make them unique catalyst carriers. New methods that modify zeolites, including sequential ion exchange, multiple isomorphic substitution, and the creation of hierarchically porous structures both during synthesis and in subsequent stages of post-synthetic processing, continue to be discovered.

Local Structures of Two-Dimensional Zeolites-Mordenite and ZSM-5-Probed by Multinuclear NMR.

Mesostructured pillared zeolite materials in the form of lamellar phases with a crystal structure of mordenite (MOR) and ZSM-5 (MFI) were grown using CTAB as an agent that creates mesopores, in a one-pot synthesis; then into the CTAB layers separating the 2D zeolite plates were introduced by diffusion the TEOS molecules which were further hydrolyzed, and finally the material was annealed to remove the organic phase, leaving the 2D zeolite plates separated by pillars of silicon dioxide. To monitor the successive structural changes and the state of the atoms of the zeolite framework and organic compounds at all the steps of the synthesis of pillared MOR and MFI zeolites, the nuclear magnetic resonance method (NMR) with magic angle spinning (MAS) was applied. The Al and Si MAS NMR spectra confirm the regularity of the zeolite frameworks of the as synthetized materials.

New Insight on the Formation of Sodium Titanates 1D Nanostructures and Its Application on CO Hydrogenation.

The aim of this work is focused on the study of a series of non-traditional catalytic nanomaterials to transform greenhouse CO gas into added-value products. We found encouraging results of CO hydrogenation activity over sodium titanates with different morphologies. The yield to methanol increases with the increase in the Na incorporated in the nanostructures confirming the proposed mechanism.

Comprehensive Analysis of the Copper Exchange Implemented in Ammonia and Protonated Forms of Mordenite Using Microwave and Conventional Methods.

This article presents the results of a comprehensive study of copper-exchanged mordenite samples prepared from its ammonia and protonated forms (Si/Al = 10) using two different ion exchange methods: conventional and microwave (MW)-assisted. The protonated H-MOR-10 sample was obtained by calcination of commercial NHMOR-10; in this case, a slight degradation of the mordenite framework was observed, but the resulting defects were partially restored after the first ion-exchange procedure of protons for copper ions. The level of copper exchange in the studied materials was found to be limited to 70%.